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	<title>Daily Bulletin &#187; Altitude</title>
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		<title>Ballistics &#8212; How Altitude and Air Pressure Affect Bullet Flight</title>
		<link>https://bulletin.accurateshooter.com/2025/11/ballistics-how-altitude-and-air-pressure-affect-bullet-flight/</link>
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		<pubDate>Thu, 20 Nov 2025 08:21:39 +0000</pubDate>
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		<description><![CDATA[Trajectory of Bullet fired at Sea Level Trajectory of Bullet fired at 20,000 feet You can do your own experimental calculations using JBM Online Ballistics (free to use). Here is an extreme example, with two printouts (generated with Point Blank software), one showing bullet trajectory at sea level (0&#8242; altitude) and one at 20,000 feet. [&#8230;]]]></description>
				<content:encoded><![CDATA[<blockquote><p><center><b>Trajectory of Bullet fired at Sea Level</b><br />
<img width="500" height="200" src="https://accurateshooter.net/Blog/altitude0x350a.png"></center></p>
<p><center><b>Trajectory of Bullet fired at 20,000 feet</b><br />
<img width="500" height="200" src="https://accurateshooter.net/Blog/altitude20000x350b.png"></center></p>
<p>You can do your own experimental calculations using <a href="https://www.jbmballistics.com/ballistics/calculators/calculators.shtml" target="new">JBM Online Ballistics</a> (free to use). Here is an extreme example, with two printouts (generated with Point Blank software), one showing bullet trajectory at sea level (0&#8242; altitude) and one at 20,000 feet. For demonstration sake, we assigned a low 0.2 BC to the bullet, with a velocity of 3000 fps.</p></blockquote>
<p><img align="right" hspace="6" src="https://accurateshooter.net/Blog/suuntoalt.jpg" alt="Suunto Altimeter">One of our readers asked &#8220;What effect does altitude have on the flight of a bullet?&#8221; The simplistic answer is that, <strong>at higher altitudes, the air is thinner (lower density), so there is less drag</strong> on the bullet. This means that the amount of bullet drop is less at any given flight distance from the muzzle. Since the force of gravity is essentially constant on the earth&#8217;s surface (for practical purposes), the bullet&#8217;s downward acceleration doesn&#8217;t change, but a bullet launched at a higher altitude is able to fly slightly farther (in the thinner air) for every increment of downward movement. Effectively, the bullet behaves as if it has a higher ballistic coefficient.</p>
<p>Forum member Milanuk explains that the <strong>key factor is not altitude, but rather air pressure</strong>. Milanuk writes:</p>
<p>&#8220;In basic terms, as your altitude increases, the density of the air the bullet must travel through decreases, thereby reducing the drag on the bullet. Generally, the higher the altitude, the less the bullet will drop. For example, I shoot at a couple ranges here in the Pacific Northwest. Both are at 1000&#8242; ASL or less. I&#8217;ll need about 29-30 MOA to get from 100 yard to 1000 yards with a Berger 155gr VLD @ 2960fps. By contrast, in Raton, NM, located at 6600&#8242; ASL, I&#8217;ll only need about 24-25 MOA to do the same. That&#8217;s a significant difference.</p>
<p>Note that <strong>it is the barometric pressure that really matters, not simply the nominal altitude</strong>. The barometric pressure will indicate the reduced pressure from a higher altitude, but it will also show you the pressure changes as a front moves in, etc. which can play havoc w/ your calculated come-ups. Most altimeters are simply barometers that read in feet instead of inches of mercury.&#8221;</p>
<p>As Milanuk states, it is NOT altitude per se, but the LOCAL barometric pressure (sometimes called &#8220;station pressure&#8221;) that is key. The two atmospheric conditions that most effect bullet flight are air temperature, and barometric pressure. Normally, humidity has a negligible effect.</p>
<p>It&#8217;s important to remember that the barometric pressure reported on the radio (or internet) may be stated as a sea level equivalency. So in Denver (at 6,000 feet amsl), if the local pressure is 24&#8243;, the radio will report the barometric pressure to be 30&#8243;. If you do high altitude shooting at long range, bring along a Kestrel, or remember to mentally correct the radio station&#8217;s pressure, by 1&#8243; per 1,000 feet.&#8221;</p>
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		<title>Access 60+ Authoritative Sierra Ballistics Articles for FREE</title>
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		<pubDate>Sat, 28 Dec 2024 11:59:23 +0000</pubDate>
		<dc:creator><![CDATA[Editor]]></dc:creator>
				<category><![CDATA[- Articles]]></category>
		<category><![CDATA[Gear Review]]></category>
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		<description><![CDATA[Need some informative reading material for winter days? Here&#8217;s a vast resource available free from Sierra Bullets. Here are links to over 60 articles with information on bullets, ballistic coefficients, wind drift, up/down angles, temperature effects, tailwind effects and much more. Most of these resources come from the respected Sierra Reloading Manuals, 4th and 5th [&#8230;]]]></description>
				<content:encoded><![CDATA[<p><a href="https://www.sierrabullets.com/exterior-ballistics/" target="_blank"><img src="http://accurateshooter.net/pix/sierra23ball01.jpg" alt="Sierra Bullets Ballistics Resources"></a></p>
<p><big>Need some informative reading material for winter days? Here&#8217;s a vast resource available free from <a href="https://www.sierrabullets.com/" target="_blank">Sierra Bullets</a>. Here are links to over 60 articles with information on bullets, ballistic coefficients, wind drift, up/down angles, temperature effects, tailwind effects and much more. Most of these resources come from the respected Sierra Reloading Manuals, 4th and 5th Editions. There are enough articles to read one per week for a year!</p>
<p><strong>Major Ballistics Reference Articles</strong><br />
<a href="https://www.sierrabullets.com/wp-content/uploads/2018/10/the_ballistic_coefficient.pdf">The Ballistic Coefficient</a> by William T. McDonald &amp; Ted C. Almgren (Adobe .PDF)<br />
<a href="https://www.sierrabullets.com/wp-content/uploads/2018/10/Deflections-and-Drift-of-a-Bullet-in-a-Crosswind-.pdf">Deflections and Drift of a Bullet in a Crosswind</a> by William T. McDonald (Adobe .PDF)<br />
<a href="https://www.sierrabullets.com/exterior-ballistics/inclined-fire/">Inclined Fire</a> by William T. McDonald</p>
<table border="0" cellpadding="4" width="600">
<tr>
<td>
<p><strong>Table of Exterior Ballistic Coefficients<br />
(5th Edition Reloading Manual)</strong><br />
<a href="https://www.sierrabullets.com/exterior-ballistics/rifle-exterior-ballistics/">Rifle</a><br />
<a href="https://www.sierrabullets.com/exterior-ballistics/sierra-handgun-coefficient-listing/">Handgun</a><br />
<a href="https://www.sierrabullets.com/exterior-ballistics/22-rimfire-ballistic-coefficients/">.22 Rimfire</a></p>
</td>
<td>
<p><strong>Exterior Ballistic Tables<br />
(4th Edition Reloading Manual)</strong><br />
<a href="https://www.sierrabullets.com/exterior-ballistics/rifle-tables-select-by-bullet/">Rifle Tables &#8211; Select by Bullet</a><br />
<a href="https://www.sierrabullets.com/exterior-ballistics/handgun-tables-select-by-bullet/">Handgun Tables &#8211; Select by Bullet</a><br />
<a href="https://www.sierrabullets.com/exterior-ballistics/silhouette-tables-select-by-bullet/">Silhouette Tables &#8211; Select by Bullet</a></p>
</td>
</tr>
</table>
<p><strong>5th Edition Manual Exterior Ballistics Section</strong><br />
Section 1.0 <a href="https://www.sierrabullets.com/exterior-ballistics/1-0-introduction/">Introduction</a><br />
Section 2-2.1 <a href="https://www.sierrabullets.com/exterior-ballistics/2-0-the-ballistic-coefficient/">The Ballistic Coefficient Explained</a><br />
Section 2.2 <a href="https://www.sierrabullets.com/exterior-ballistics/2-2-bigger-is-not-always-better/">Bigger Is Not Always Better</a><br />
Section 2.3 <a href="https://www.sierrabullets.com/exterior-ballistics/2-3-how-the-ballistic-coefficient-is-measured/">How the Ballistic Coefficient is Measured</a><br />
Section 2.3.1.1 <a href="https://www.sierrabullets.com/exterior-ballistics/2-3-1-initial-velocity-and-final-velocity-method/">Measurement Procedure</a><br />
Section 2.3.1.2 <a href="https://www.sierrabullets.com/exterior-ballistics/2-3-1-2-important-precautions-and-points-to-consider/">Important Precautions and Points to Consider</a><br />
Section 2.3.2 <a href="https://www.sierrabullets.com/exterior-ballistics/2-3-2-initial-velocity-and-time-of-flight-method/">Initial Velocity and Time of Flight Method</a><br />
Section 2.3.3 <a href="https://www.sierrabullets.com/exterior-ballistics/2-3-3-doppler-radar-method/">Doppler Radar Method</a><br />
Section 2.4 <a href="https://www.sierrabullets.com/exterior-ballistics/2-4-lessons-learned-from-ballistic-coefficient-testing/">Lessons Learned from Ballistic Coefficient Testing</a><br />
Section 2.5 <a href="https://www.sierrabullets.com/exterior-ballistics/17302-2/">Examples of Ballistic Coefficient Measurements</a><br />
Section 3.0 <a href="https://www.sierrabullets.com/exterior-ballistics/3-0-exterior-ballistic-effects-on-bullet-flight/">Exterior Ballistic Effects on Bullet Flight</a><br />
Section 3.1 <a href="https://www.sierrabullets.com/exterior-ballistics/3-1-effects-of-altitude-and-atmospheric-conditions/">Effects of Altitude and Atmospheric Conditions</a><br />
Section 3.2 <a href="https://www.sierrabullets.com/exterior-ballistics/3-2-effects-of-winds/">Effects of Wind</a><br />
Section 3.3 <a href="https://www.sierrabullets.com/exterior-ballistics/3-3-effects-of-shooting-uphill-or-downhill/">Effects of Shooting Uphill or Downhill</a><br />
Section 3.4-3.4.1 <a href="https://www.sierrabullets.com/exterior-ballistics/3-4-trajectory-considerations-for-sighting-in-a-gun/">Trajectory Considerations for Sighting in a Gun</a><br />
Section 3.4.2 <a href="https://www.sierrabullets.com/exterior-ballistics/3-4-2-determining-zero-range-from-firing-test-results/">Determining Zero Range from Firing Test Results</a><br />
Section 3.4.3 <a href="https://www.sierrabullets.com/exterior-ballistics/3-4-3-sighting-in-for-a-change-in-shooting-location/">Sighting in for a Change in Shooting Location</a><br />
Section 3.5 <a href="https://www.sierrabullets.com/exterior-ballistics/3-5-point-blank-range/">Point Blank Range</a><br />
Section 3.6 <a href="https://www.sierrabullets.com/exterior-ballistics/3-6-maximum-horizontal-range-of-a-gun/">Maximum Horizontal Range of a Gun</a><br />
Section 3.7 <a href="https://www.sierrabullets.com/exterior-ballistics/3-7-maximum-height-of-fire-of-a-gun/">Maximum Height of Fire of a Gun</a><br />
Section 4.0 <a href="https://www.sierrabullets.com/exterior-ballistics/4-0-six-degree-of-freedom-effects-on-bullet-flight/">Six Degree of Freedom Effects on Bullet Flight</a><br />
Section 4.1 <a href="https://www.sierrabullets.com/exterior-ballistics/4-1-basic-physical-concepts/">Basic Physical Concepts</a><br />
Section 4.2 <a href="https://www.sierrabullets.com/exterior-ballistics/4-2-yaw-of-repose-and-resulting-crossrange-deflection/">Yaw of Repose and Resulting Crossrange Deflection</a><br />
Section 4.3 <a href="https://www.sierrabullets.com/exterior-ballistics/4-3-turning-of-a-bullet-to-follow-a-crosswind-and-resulting-deflections/">Turning of a Bullet to Follow a Crosswind and Resulting Deflections</a><br />
Section 4.4 <a href="https://www.sierrabullets.com/exterior-ballistics/4-4-turning-of-a-bullet-to-follow-a-vertical-wind-and-resulting-deflections/">Turning of a Bullet to Follow a Vertical Wind and Resulting Deflections</a><br />
Section 5.0 <a href="https://www.sierrabullets.com/exterior-ballistics/5-0-trajectory-tables/">Trajectory Tables</a><br />
Section 6.0 <a href="https://www.sierrabullets.com/exterior-ballistics/6-0-sierras-infinity-exterior-ballistics-software/">Sierra&#8217;s Infinity Exterior Ballistics Software</a></p>
<p><strong>4th Edition Manual Exterior Ballistics Section</strong><br />
Section 2.0 <a href="https://www.sierrabullets.com/exterior-ballistics/2-0-introduction/">Introduction</a><br />
Section 3.0 <a href="https://www.sierrabullets.com/exterior-ballistics/3-0-historical-summary/">Historical Summary</a><br />
Section 4.0 <a href="https://www.sierrabullets.com/exterior-ballistics/4-0-the-ballistic-coefficient/">The Ballistic Coefficient</a><br />
Section 4.1 <a href="https://www.sierrabullets.com/exterior-ballistics/4-1-basic-definitions/">Basic Definitions</a><br />
Section 4.2 <a href="https://www.sierrabullets.com/exterior-ballistics/4-2-ballistic-coefficient-effects-on-bullet-trajectories/">Ballistic Coefficients Effects on Bullet Trajectories</a><br />
Section 4.3 <a href="https://www.sierrabullets.com/exterior-ballistics/4-3-how-the-ballistic-coefficient-is-measured-by-firing-tests/">How the Ballistic Coefficient is Measured by Firing Tests</a><br />
Section 4.4 <a href="https://www.sierrabullets.com/exterior-ballistics/4-4-lessons-learned-from-ballistic-coefficient-measurements/">Lessons Learned From Ballistic Coefficient Measurements</a><br />
Section 4.5 <a href="https://www.sierrabullets.com/exterior-ballistics/4-5-ballistic-coefficient-variations-with-muzzle-velocity-near-the-speed-of-sound/">Ballistic Coefficient Variations with Muzzle Velocity near the Speed of Sound</a><br />
Section 4.6 <a href="https://www.sierrabullets.com/exterior-ballistics/4-6-ballistic-coefficient-dependence-on-coning-motion/">Ballistic Coefficient Dependence on Coning Motion</a><br />
Section 5.0 <a href="https://www.sierrabullets.com/exterior-ballistics/5-0-exterior-ballistics-topics/">Exterior Ballistics Topics</a><br />
Section 5.1 <a href="https://www.sierrabullets.com/exterior-ballistics/5-1-effects-of-altitude-and-atmospheric-conditions/">Effects of Altitude and Atmospheric Conditions</a><br />
Section 5.2 <a href="https://www.sierrabullets.com/exterior-ballistics/5-2-effects-of-altitude-and-uphill-downhill-shooting/">Effects of Altitude and Uphill/Downhill Shooting</a><br />
Section 5.3 <a href="https://www.sierrabullets.com/exterior-ballistics/5-3-wind-effects/">Wind Effects</a><br />
Section 5.3.1 <a href="https://www.sierrabullets.com/exterior-ballistics/5-3-1-headwinds-and-tailwinds/">Headwinds and Tailwinds</a><br />
Section 5.3.2 <a href="https://www.sierrabullets.com/exterior-ballistics/5-3-2-crosswinds/">Crosswinds</a><br />
Section 5.3.3 <a href="https://www.sierrabullets.com/exterior-ballistics/5-3-3-winds-from-any-direction/">Winds from Any Direction</a><br />
Section 5.4 <a href="https://www.sierrabullets.com/exterior-ballistics/5-4-changing-the-zero-range/">Changing the Zero Range</a><br />
Section 5.5 <a href="https://www.sierrabullets.com/exterior-ballistics/5-5-point-blank-range/">Point Blank Range</a><br />
Section 5.6 <a href="https://www.sierrabullets.com/exterior-ballistics/5-6-muzzle-velocity-dependence-on-cartridge-temperature/">Muzzle Velocity Dependence on Cartridge Temperature</a><br />
Section 6.0 <a href="https://www.sierrabullets.com/exterior-ballistics/6-0-equations-of-bullet-flight/">Equations of Bullet Flight</a><br />
Section 6.1 <a href="https://www.sierrabullets.com/exterior-ballistics/6-1-differential-equations-of-bullet-motion/">Differential Equations of Bullet Motion</a><br />
Section 6.2 <a href="https://www.sierrabullets.com/exterior-ballistics/6-2-drag-force-and-the-drag-function/">Drag Force and the Drag Function</a><br />
Section 6.3/Section 6.3.1 <a href="https://www.sierrabullets.com/exterior-ballistics/6-3-siaccis-method-6-3-1-the-change-of-independent-variables/">Siacci&#8217;s Method</a><a href="https://www.sierrabullets.com/exterior-ballistics/6-3-siaccis-method-6-3-1-the-change-of-independent-variables/">/The Change of Independent Variables</a><br />
Section 6.3.2 <a href="https://www.sierrabullets.com/exterior-ballistics/6-3-2-the-assumption/">The Assumption</a><br />
Section 6.4 <a href="https://www.sierrabullets.com/exterior-ballistics/6-4-mayevskis-analytical-form-of-the-drag-mode/">Mayevski&#8217;s Analytical Form of the Drag Model</a><br />
Section 6.5 <a href="https://www.sierrabullets.com/exterior-ballistics/6-5-closed-form-solutions-for-trajectory-parameters/">Closed-Form Solutions for Trajectory Parameters</a><br />
Section 6.6 <a href="https://www.sierrabullets.com/exterior-ballistics/6-6-other-useful-equations/">Other Useful Equations</a><br />
Section 6.6.1 <a href="https://www.sierrabullets.com/exterior-ballistics/6-6-1-references/">References</a></p>
<p></big></p>
<p><a href="https://www.sierrabullets.com/exterior-ballistics/" target="_blank"><img src="http://accurateshooter.net/pix/sierra23ball03.jpg" alt="Sierra Bullets Ballistics Resources"></a></p>
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		<title>How Altitude Affects Ballistics &#8212; Important for Hunters</title>
		<link>https://bulletin.accurateshooter.com/2024/08/how-altitude-affects-ballistics-important-for-hunters/</link>
		<comments>https://bulletin.accurateshooter.com/2024/08/how-altitude-affects-ballistics-important-for-hunters/#comments</comments>
		<pubDate>Fri, 16 Aug 2024 05:22:25 +0000</pubDate>
		<dc:creator><![CDATA[Editor]]></dc:creator>
				<category><![CDATA[- Articles]]></category>
		<category><![CDATA[Bullets, Brass, Ammo]]></category>
		<category><![CDATA[Hunting/Varminting]]></category>
		<category><![CDATA[Tech Tip]]></category>
		<category><![CDATA[Air Pressure]]></category>
		<category><![CDATA[Altitude]]></category>
		<category><![CDATA[ballistics]]></category>
		<category><![CDATA[BC]]></category>
		<category><![CDATA[Coefficient]]></category>
		<category><![CDATA[Density Altitude]]></category>
		<category><![CDATA[Kestrel]]></category>
		<category><![CDATA[Monte Milanuk]]></category>
		<category><![CDATA[Trajectory]]></category>

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		<description><![CDATA[Photo shows the new ZEISS LRP S5 318-50 first focal plane (FFP) scope. &#8220;A bullet launched at a higher altitude is able to fly slightly farther (in the thinner air) for every increment of downward movement. Effectively, the bullet behaves as if it has a higher ballistic coefficient.&#8221; A few seasons back a good friend [&#8230;]]]></description>
				<content:encoded><![CDATA[<p><img src="https://accurateshooter.net/pix/altitude22x1.jpg" alt="altitude ballistics zeiss LRP S5 318-50 FFP scope"><br />
<i>Photo shows the new <a href="http://www.zeiss.com/lrp-s5" target="_blank">ZEISS LRP S5 318-50</a> first focal plane (FFP) scope.</i></p>
<blockquote><p>&#8220;A bullet launched at a higher altitude is able to fly slightly farther (in the thinner air) for every increment of downward movement. Effectively, the bullet behaves as if it has a higher ballistic coefficient.&#8221;</p></blockquote>
<p><big>A few seasons back a good friend ventured to the high country of Colorado to pursue elk. He recently zeroed his rifle in California, at a range just a few hundred feet Above Mean Sea Level (AMSL). He wondered if the higher altitude in Colorado could alter his ballistics. The answer is a definite yes. However the good news is that <strong>free ballistics calculators</strong> can help you plot reliable drop charts for various shooting locations, high or low.</big></p>
<p><img class="alignright" hspace="12" src="https://accurateshooter.net/Blog/suuntoalt.jpg" alt="Suunto Altimeter">The question has been posed: &#8220;What effect does altitude have on the flight of a bullet?&#8221; The simplistic answer is that, <strong>at higher altitudes, the air is thinner (lower density), so there is less drag</strong> on the bullet. This means that the amount of bullet drop is less at any given flight distance from the muzzle. Since the force of gravity is essentially constant on the earth&#8217;s surface (for practical purposes), the bullet&#8217;s downward acceleration doesn&#8217;t change, but a bullet launched at a higher altitude is able to fly slightly farther (in the thinner air) for every increment of downward movement. Effectively, at higher altitudes, the bullet behaves as if it has a<strong> higher ballistic coefficient</strong>.</p>
<p>Forum member Milanuk explains that the <strong>key factor is not altitude, but rather air pressure</strong>. Milanuk writes:</p>
<blockquote><p><big>&#8220;In basic terms, as your altitude increases, the density of the air the bullet must travel through decreases, thereby reducing the drag on the bullet. Generally, the higher the altitude, the less the bullet will drop. For example, I shoot at a couple ranges here in the Pacific Northwest. Both are at 1000&#8242; AMSL (Above Mean Sea Level) or less. I&#8217;ll need about 29-30 MOA to get from 100 yards to 1000 yards with a Berger 155gr VLD at 2960 fps. By contrast, in Raton, NM, located at 6600&#8242; AMSL, I&#8217;ll only need about 24-25 MOA to do the same. That&#8217;s a significant difference.</p>
<p>Note that <strong>it is the barometric pressure that really matters, not simply the nominal altitude</strong>. The barometric pressure will indicate the reduced pressure from a higher altitude, but it will also show you the pressure changes as a front moves in, etc. which can play havoc w/ your calculated come-ups. Most altimeters are simply barometers that read in feet instead of inches of mercury.&#8221;</big></p></blockquote>
<p>As Milanuk states, it is NOT altitude per se, but the <strong>LOCAL barometric pressure</strong> (sometimes called &#8220;station pressure&#8221;) that is key. The two atmospheric conditions that most effect bullet flight are air temperature, and barometric pressure. Normally, humidity has a negligible effect. It&#8217;s important to remember that the barometric pressure reported on the radio (or internet) may be stated as a sea level equivalency. So in Denver (at 6,000 feet AMSL), if the local pressure is 24&#8243;, the radio will report the barometric pressure to be 30&#8243;. If you do high altitude shooting at long range, <strong>bring along a Kestrel</strong>, or remember to mentally correct the radio station&#8217;s pressure, by 1&#8243; per 1,000 feet.</p>
<blockquote><p><center><b>Trajectory of Bullet fired at Sea Level</b><br />
<img width="500" height="200" src="https://accurateshooter.net/Blog/altitude0x350a.png"></center></p>
<p><center><b>Trajectory of Bullet fired at 20,000 feet</b><br />
<img width="500" height="200" src="http://accurateshooter.net/Blog/altitude20000x350b.png"></center></p>
<p>You can do your own experimental calculations using <a href="https://www.jbmballistics.com/ballistics/calculators/calculators.shtml" target="new">JBM Online Ballistics</a> (free to use). Here is an extreme example, with two printouts (generated with Point Blank software), one showing bullet trajectory at sea level (0&#8242; altitude) and one at 20,000 feet. For demonstration sake, we assigned a low 0.2 BC to the bullet, with a velocity of 3000 fps.</p></blockquote>
<p>To learn more about all aspects of Exterior Ballistics, Hornady has a useful discussion of <a href="https://www.hornady.com/team-hornady/ballistic-calculators/ballistic-resources/external-ballistics" target="new">External Ballistics</a> including the effects of altitude and temperature. To dig deeper, <a href="https://www.sierrabullets.com/exterior-ballistics/" target="_blank">Sierra Bullets</a> has a comprehensive <a href="https://www.sierrabullets.com/exterior-ballistics/" target="_blank">Exterior Ballistics Resource Page</a> with multiple sections from the Sierra Manual (4th and 5th Editions), including:</p>
<p>Section 3.0: <a href="https://www.sierrabullets.com/exterior-ballistics/3-0-exterior-ballistic-effects-on-bullet-flight/" target="_blank">Exterior Ballistic Effects on Bullet Flight</a><br />
Section 3.1: <a href="https://www.sierrabullets.com/exterior-ballistics/3-1-effects-of-altitude-and-atmospheric-conditions/" target="_blank">Effects of Altitude and Atmospheric Conditions</a><br />
Section 3.2: <a href="https://www.sierrabullets.com/exterior-ballistics/3-2-effects-of-winds/" target="_blank">Effects of Wind</a><br />
Section 3.3: <a href="https://www.sierrabullets.com/exterior-ballistics/3-3-effects-of-shooting-uphill-or-downhill/" target="_blank">Effects of Shooting Uphill or Downhill</a></p>
<p>Example from Section 3.0: &#8220;When a bullet flies through the air, two types of forces act on the bullet to determine its path (trajectory) through the air. The first is gravitational force; the other is aerodynamics. Several kinds of aerodynamic forces act on a bullet: drag, lift, side forces, Magnus force, spin damping force, pitch damping force, and Magnus cross force. The most important of these aerodynamic forces is drag. All the others are very small in comparison when the bullet is spin-stabilized.&#8221;</p>
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		<title>How Altitude Affects Ballistics &#8212; Hunters Take Note</title>
		<link>https://bulletin.accurateshooter.com/2023/09/how-altitude-affects-ballistics-hunters-take-note/</link>
		<comments>https://bulletin.accurateshooter.com/2023/09/how-altitude-affects-ballistics-hunters-take-note/#comments</comments>
		<pubDate>Thu, 28 Sep 2023 15:10:24 +0000</pubDate>
		<dc:creator><![CDATA[Editor]]></dc:creator>
				<category><![CDATA[Bullets, Brass, Ammo]]></category>
		<category><![CDATA[Hunting/Varminting]]></category>
		<category><![CDATA[Tech Tip]]></category>
		<category><![CDATA[Air Pressure]]></category>
		<category><![CDATA[Altitude]]></category>
		<category><![CDATA[ballistics]]></category>
		<category><![CDATA[BC]]></category>
		<category><![CDATA[Coefficient]]></category>
		<category><![CDATA[Density Altitude]]></category>
		<category><![CDATA[Kestrel]]></category>
		<category><![CDATA[Trajectory]]></category>

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		<description><![CDATA[Photo shows the new ZEISS LRP S5 318-50 first focal plane (FFP) scope. &#8220;A bullet launched at a higher altitude is able to fly slightly farther (in the thinner air) for every increment of downward movement. Effectively, the bullet behaves as if it has a higher ballistic coefficient.&#8221; It&#8217;s hunting season, and we have a [&#8230;]]]></description>
				<content:encoded><![CDATA[<p><img src="https://accurateshooter.net/pix/altitude21x1.jpg" alt="altitude ballistics zeiss LRP S5 318-50 FFP scope"><br />
<i>Photo shows the new <a href="http://www.zeiss.com/lrp-s5" target="_blank">ZEISS LRP S5 318-50</a> first focal plane (FFP) scope.</i></p>
<blockquote><p>&#8220;A bullet launched at a higher altitude is able to fly slightly farther (in the thinner air) for every increment of downward movement. Effectively, the bullet behaves as if it has a higher ballistic coefficient.&#8221;</p></blockquote>
<p>It&#8217;s hunting season, and we have a friend who wants to go the high country of Colorado to pursue elk. He recently zeroed his rifle in California, at a range just a few hundred feet Above Mean Sea Level (AMSL). He wondered if the higher altitude in Colorado could alter his ballistics. The answer is a definite yes. However the good news is that free ballistics calculators can help you plot reliable drop charts for various shooting locations, high or low.</p>
<p><img class="alignright" hspace="12" src="http://accurateshooter.net/Blog/suuntoalt.jpg" alt="Suunto Altimeter">The question has been posed: &#8220;What effect does altitude have on the flight of a bullet?&#8221; The simplistic answer is that, <strong>at higher altitudes, the air is thinner (lower density), so there is less drag</strong> on the bullet. This means that the amount of bullet drop is less at any given flight distance from the muzzle. Since the force of gravity is essentially constant on the earth&#8217;s surface (for practical purposes), the bullet&#8217;s downward acceleration doesn&#8217;t change, but a bullet launched at a higher altitude is able to fly slightly farther (in the thinner air) for every increment of downward movement. Effectively, at higher altitudes, the bullet behaves as if it has a<strong> higher ballistic coefficient</strong>.</p>
<p>Forum member Milanuk explains that the <strong>key factor is not altitude, but rather air pressure</strong>. Milanuk writes:</p>
<blockquote><p><big>&#8220;In basic terms, as your altitude increases, the density of the air the bullet must travel through decreases, thereby reducing the drag on the bullet. Generally, the higher the altitude, the less the bullet will drop. For example, I shoot at a couple ranges here in the Pacific Northwest. Both are at 1000&#8242; AMSL (Above Mean Sea Level) or less. I&#8217;ll need about 29-30 MOA to get from 100 yards to 1000 yards with a Berger 155gr VLD at 2960 fps. By contrast, in Raton, NM, located at 6600&#8242; AMSL, I&#8217;ll only need about 24-25 MOA to do the same. That&#8217;s a significant difference.</p>
<p>Note that <strong>it is the barometric pressure that really matters, not simply the nominal altitude</strong>. The barometric pressure will indicate the reduced pressure from a higher altitude, but it will also show you the pressure changes as a front moves in, etc. which can play havoc w/ your calculated come-ups. Most altimeters are simply barometers that read in feet instead of inches of mercury.&#8221;</big></p></blockquote>
<p>As Milanuk states, it is NOT altitude per se, but the <strong>LOCAL barometric pressure</strong> (sometimes called &#8220;station pressure&#8221;) that is key. The two atmospheric conditions that most effect bullet flight are air temperature, and barometric pressure. Normally, humidity has a negligible effect. It&#8217;s important to remember that the barometric pressure reported on the radio (or internet) may be stated as a sea level equivalency. So in Denver (at 6,000 feet AMSL), if the local pressure is 24&#8243;, the radio will report the barometric pressure to be 30&#8243;. If you do high altitude shooting at long range, <strong>bring along a Kestrel</strong>, or remember to mentally correct the radio station&#8217;s pressure, by 1&#8243; per 1,000 feet.</p>
<blockquote><p><center><b>Trajectory of Bullet fired at Sea Level</b><br />
<img width="500" height="200" src="http://accurateshooter.net/Blog/altitude0x350a.png"></center></p>
<p><center><b>Trajectory of Bullet fired at 20,000 feet</b><br />
<img width="500" height="200" src="http://accurateshooter.net/Blog/altitude20000x350b.png"></center></p>
<p>You can do your own experimental calculations using <a href="http://www.jbmballistics.com/ballistics/calculators/calculators.shtml" target="new">JBM Online Ballistics</a> (free to use). Here is an extreme example, with two printouts (generated with Point Blank software), one showing bullet trajectory at sea level (0&#8242; altitude) and one at 20,000 feet. For demonstration sake, we assigned a low 0.2 BC to the bullet, with a velocity of 3000 fps.</p></blockquote>
<p>To learn more about all aspects of Exterior Ballistics, Hornady has a useful discussion of <a href="https://www.hornady.com/team-hornady/ballistic-calculators/ballistic-resources/external-ballistics" target="new">External Ballistics</a> including the effects of altitude and temperature. To dig deeper, <a href="https://www.sierrabullets.com/exterior-ballistics/" target="_blank">Sierra Bullets</a> has a comprehensive <a href="https://www.sierrabullets.com/exterior-ballistics/" target="_blank">Exterior Ballistics Resource Page</a> with multiple sections from the Sierra Manual (4th and 5th Editions), including:</p>
<p>Section 3.0: <a href="https://www.sierrabullets.com/exterior-ballistics/3-0-exterior-ballistic-effects-on-bullet-flight/" target="_blank">Exterior Ballistic Effects on Bullet Flight</a><br />
Section 3.1: <a href="https://www.sierrabullets.com/exterior-ballistics/3-1-effects-of-altitude-and-atmospheric-conditions/" target="_blank">Effects of Altitude and Atmospheric Conditions</a><br />
Section 3.2: <a href="https://www.sierrabullets.com/exterior-ballistics/3-2-effects-of-winds/" target="_blank">Effects of Wind</a><br />
Section 3.3: <a href="https://www.sierrabullets.com/exterior-ballistics/3-3-effects-of-shooting-uphill-or-downhill/" target="_blank">Effects of Shooting Uphill or Downhill</a></p>
<p>Example from Section 3.0: &#8220;When a bullet flies through the air, two types of forces act on the bullet to determine its path (trajectory) through the air. The first is gravitational force; the other is aerodynamics. Several kinds of aerodynamic forces act on a bullet: drag, lift, side forces, Magnus force, spin damping force, pitch damping force, and Magnus cross force. The most important of these aerodynamic forces is drag. All the others are very small in comparison when the bullet is spin-stabilized.&#8221;</p>
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		<title>Sierra Ballistics Resources &#8212; 60+ Authoritative Articles for FREE</title>
		<link>https://bulletin.accurateshooter.com/2023/01/sierra-ballistics-resources-60-authoritative-articles-for-free/</link>
		<comments>https://bulletin.accurateshooter.com/2023/01/sierra-ballistics-resources-60-authoritative-articles-for-free/#comments</comments>
		<pubDate>Sat, 21 Jan 2023 14:00:08 +0000</pubDate>
		<dc:creator><![CDATA[Editor]]></dc:creator>
				<category><![CDATA[- Articles]]></category>
		<category><![CDATA[Bullets, Brass, Ammo]]></category>
		<category><![CDATA[Shooting Skills]]></category>
		<category><![CDATA[Tech Tip]]></category>
		<category><![CDATA[Altitude]]></category>
		<category><![CDATA[Ballistics Coefficients]]></category>
		<category><![CDATA[BC]]></category>
		<category><![CDATA[Exterior Ballistics]]></category>
		<category><![CDATA[Sierra Bullets]]></category>
		<category><![CDATA[Sierra Reloading Manual]]></category>
		<category><![CDATA[Wind Drift]]></category>

		<guid isPermaLink="false">http://bulletin.accurateshooter.com/?p=68295</guid>
		<description><![CDATA[Need some informative reading material for winter days? Here&#8217;s a vast resource available free from Sierra Bullets. Here are links to over 60 articles with information on bullets, ballistic coefficients, wind drift, up/down angles, temperature effects, tailwind effects and much more. Most of these resources come from the respected Sierra Reloading Manuals, 4th and 5th [&#8230;]]]></description>
				<content:encoded><![CDATA[<p><a href="https://www.sierrabullets.com/exterior-ballistics/" target="_blank"><img src="http://accurateshooter.net/pix/sierra23ball01.jpg" alt="Sierra Bullets Ballistics Resources"></a></p>
<p><big>Need some informative reading material for winter days? Here&#8217;s a vast resource available free from <a href="https://www.sierrabullets.com/" target="_blank">Sierra Bullets</a>. Here are links to over 60 articles with information on bullets, ballistic coefficients, wind drift, up/down angles, temperature effects, tailwind effects and much more. Most of these resources come from the respected Sierra Reloading Manuals, 4th and 5th Editions. There are enough articles to read one per week for a year!</p>
<p><strong>Major Ballistics Reference Articles</strong><br />
<a href="https://www.sierrabullets.com/wp-content/uploads/2018/10/the_ballistic_coefficient.pdf">The Ballistic Coefficient</a> by William T. McDonald &amp; Ted C. Almgren (Adobe .PDF)<br />
<a href="https://www.sierrabullets.com/wp-content/uploads/2018/10/Deflections-and-Drift-of-a-Bullet-in-a-Crosswind-.pdf">Deflections and Drift of a Bullet in a Crosswind</a> by William T. McDonald (Adobe .PDF)<br />
<a href="https://www.sierrabullets.com/exterior-ballistics/inclined-fire/">Inclined Fire</a> by William T. McDonald</p>
<table border="0" cellpadding="4" width="600">
<tr>
<td>
<p><strong>Table of Exterior Ballistic Coefficients<br />
(5th Edition Reloading Manual)</strong><br />
<a href="https://www.sierrabullets.com/exterior-ballistics/rifle-exterior-ballistics/">Rifle</a><br />
<a href="https://www.sierrabullets.com/exterior-ballistics/sierra-handgun-coefficient-listing/">Handgun</a><br />
<a href="https://www.sierrabullets.com/exterior-ballistics/22-rimfire-ballistic-coefficients/">.22 Rimfire</a></p>
</td>
<td>
<p><strong>Exterior Ballistic Tables<br />
(4th Edition Reloading Manual)</strong><br />
<a href="https://www.sierrabullets.com/exterior-ballistics/rifle-tables-select-by-bullet/">Rifle Tables &#8211; Select by Bullet</a><br />
<a href="https://www.sierrabullets.com/exterior-ballistics/handgun-tables-select-by-bullet/">Handgun Tables &#8211; Select by Bullet</a><br />
<a href="https://www.sierrabullets.com/exterior-ballistics/silhouette-tables-select-by-bullet/">Silhouette Tables &#8211; Select by Bullet</a></p>
</td>
</tr>
</table>
<p><strong>5th Edition Manual Exterior Ballistics Section</strong><br />
Section 1.0 <a href="https://www.sierrabullets.com/exterior-ballistics/1-0-introduction/">Introduction</a><br />
Section 2-2.1 <a href="https://www.sierrabullets.com/exterior-ballistics/2-0-the-ballistic-coefficient/">The Ballistic Coefficient Explained</a><br />
Section 2.2 <a href="https://www.sierrabullets.com/exterior-ballistics/2-2-bigger-is-not-always-better/">Bigger Is Not Always Better</a><br />
Section 2.3 <a href="https://www.sierrabullets.com/exterior-ballistics/2-3-how-the-ballistic-coefficient-is-measured/">How the Ballistic Coefficient is Measured</a><br />
Section 2.3.1.1 <a href="https://www.sierrabullets.com/exterior-ballistics/2-3-1-initial-velocity-and-final-velocity-method/">Measurement Procedure</a><br />
Section 2.3.1.2 <a href="https://www.sierrabullets.com/exterior-ballistics/2-3-1-2-important-precautions-and-points-to-consider/">Important Precautions and Points to Consider</a><br />
Section 2.3.2 <a href="https://www.sierrabullets.com/exterior-ballistics/2-3-2-initial-velocity-and-time-of-flight-method/">Initial Velocity and Time of Flight Method</a><br />
Section 2.3.3 <a href="https://www.sierrabullets.com/exterior-ballistics/2-3-3-doppler-radar-method/">Doppler Radar Method</a><br />
Section 2.4 <a href="https://www.sierrabullets.com/exterior-ballistics/2-4-lessons-learned-from-ballistic-coefficient-testing/">Lessons Learned from Ballistic Coefficient Testing</a><br />
Section 2.5 <a href="https://www.sierrabullets.com/exterior-ballistics/17302-2/">Examples of Ballistic Coefficient Measurements</a><br />
Section 3.0 <a href="https://www.sierrabullets.com/exterior-ballistics/3-0-exterior-ballistic-effects-on-bullet-flight/">Exterior Ballistic Effects on Bullet Flight</a><br />
Section 3.1 <a href="https://www.sierrabullets.com/exterior-ballistics/3-1-effects-of-altitude-and-atmospheric-conditions/">Effects of Altitude and Atmospheric Conditions</a><br />
Section 3.2 <a href="https://www.sierrabullets.com/exterior-ballistics/3-2-effects-of-winds/">Effects of Wind</a><br />
Section 3.3 <a href="https://www.sierrabullets.com/exterior-ballistics/3-3-effects-of-shooting-uphill-or-downhill/">Effects of Shooting Uphill or Downhill</a><br />
Section 3.4-3.4.1 <a href="https://www.sierrabullets.com/exterior-ballistics/3-4-trajectory-considerations-for-sighting-in-a-gun/">Trajectory Considerations for Sighting in a Gun</a><br />
Section 3.4.2 <a href="https://www.sierrabullets.com/exterior-ballistics/3-4-2-determining-zero-range-from-firing-test-results/">Determining Zero Range from Firing Test Results</a><br />
Section 3.4.3 <a href="https://www.sierrabullets.com/exterior-ballistics/3-4-3-sighting-in-for-a-change-in-shooting-location/">Sighting in for a Change in Shooting Location</a><br />
Section 3.5 <a href="https://www.sierrabullets.com/exterior-ballistics/3-5-point-blank-range/">Point Blank Range</a><br />
Section 3.6 <a href="https://www.sierrabullets.com/exterior-ballistics/3-6-maximum-horizontal-range-of-a-gun/">Maximum Horizontal Range of a Gun</a><br />
Section 3.7 <a href="https://www.sierrabullets.com/exterior-ballistics/3-7-maximum-height-of-fire-of-a-gun/">Maximum Height of Fire of a Gun</a><br />
Section 4.0 <a href="https://www.sierrabullets.com/exterior-ballistics/4-0-six-degree-of-freedom-effects-on-bullet-flight/">Six Degree of Freedom Effects on Bullet Flight</a><br />
Section 4.1 <a href="https://www.sierrabullets.com/exterior-ballistics/4-1-basic-physical-concepts/">Basic Physical Concepts</a><br />
Section 4.2 <a href="https://www.sierrabullets.com/exterior-ballistics/4-2-yaw-of-repose-and-resulting-crossrange-deflection/">Yaw of Repose and Resulting Crossrange Deflection</a><br />
Section 4.3 <a href="https://www.sierrabullets.com/exterior-ballistics/4-3-turning-of-a-bullet-to-follow-a-crosswind-and-resulting-deflections/">Turning of a Bullet to Follow a Crosswind and Resulting Deflections</a><br />
Section 4.4 <a href="https://www.sierrabullets.com/exterior-ballistics/4-4-turning-of-a-bullet-to-follow-a-vertical-wind-and-resulting-deflections/">Turning of a Bullet to Follow a Vertical Wind and Resulting Deflections</a><br />
Section 5.0 <a href="https://www.sierrabullets.com/exterior-ballistics/5-0-trajectory-tables/">Trajectory Tables</a><br />
Section 6.0 <a href="https://www.sierrabullets.com/exterior-ballistics/6-0-sierras-infinity-exterior-ballistics-software/">Sierra&#8217;s Infinity Exterior Ballistics Software</a></p>
<p><strong>4th Edition Manual Exterior Ballistics Section</strong><br />
Section 2.0 <a href="https://www.sierrabullets.com/exterior-ballistics/2-0-introduction/">Introduction</a><br />
Section 3.0 <a href="https://www.sierrabullets.com/exterior-ballistics/3-0-historical-summary/">Historical Summary</a><br />
Section 4.0 <a href="https://www.sierrabullets.com/exterior-ballistics/4-0-the-ballistic-coefficient/">The Ballistic Coefficient</a><br />
Section 4.1 <a href="https://www.sierrabullets.com/exterior-ballistics/4-1-basic-definitions/">Basic Definitions</a><br />
Section 4.2 <a href="https://www.sierrabullets.com/exterior-ballistics/4-2-ballistic-coefficient-effects-on-bullet-trajectories/">Ballistic Coefficients Effects on Bullet Trajectories</a><br />
Section 4.3 <a href="https://www.sierrabullets.com/exterior-ballistics/4-3-how-the-ballistic-coefficient-is-measured-by-firing-tests/">How the Ballistic Coefficient is Measured by Firing Tests</a><br />
Section 4.4 <a href="https://www.sierrabullets.com/exterior-ballistics/4-4-lessons-learned-from-ballistic-coefficient-measurements/">Lessons Learned From Ballistic Coefficient Measurements</a><br />
Section 4.5 <a href="https://www.sierrabullets.com/exterior-ballistics/4-5-ballistic-coefficient-variations-with-muzzle-velocity-near-the-speed-of-sound/">Ballistic Coefficient Variations with Muzzle Velocity near the Speed of Sound</a><br />
Section 4.6 <a href="https://www.sierrabullets.com/exterior-ballistics/4-6-ballistic-coefficient-dependence-on-coning-motion/">Ballistic Coefficient Dependence on Coning Motion</a><br />
Section 5.0 <a href="https://www.sierrabullets.com/exterior-ballistics/5-0-exterior-ballistics-topics/">Exterior Ballistics Topics</a><br />
Section 5.1 <a href="https://www.sierrabullets.com/exterior-ballistics/5-1-effects-of-altitude-and-atmospheric-conditions/">Effects of Altitude and Atmospheric Conditions</a><br />
Section 5.2 <a href="https://www.sierrabullets.com/exterior-ballistics/5-2-effects-of-altitude-and-uphill-downhill-shooting/">Effects of Altitude and Uphill/Downhill Shooting</a><br />
Section 5.3 <a href="https://www.sierrabullets.com/exterior-ballistics/5-3-wind-effects/">Wind Effects</a><br />
Section 5.3.1 <a href="https://www.sierrabullets.com/exterior-ballistics/5-3-1-headwinds-and-tailwinds/">Headwinds and Tailwinds</a><br />
Section 5.3.2 <a href="https://www.sierrabullets.com/exterior-ballistics/5-3-2-crosswinds/">Crosswinds</a><br />
Section 5.3.3 <a href="https://www.sierrabullets.com/exterior-ballistics/5-3-3-winds-from-any-direction/">Winds from Any Direction</a><br />
Section 5.4 <a href="https://www.sierrabullets.com/exterior-ballistics/5-4-changing-the-zero-range/">Changing the Zero Range</a><br />
Section 5.5 <a href="https://www.sierrabullets.com/exterior-ballistics/5-5-point-blank-range/">Point Blank Range</a><br />
Section 5.6 <a href="https://www.sierrabullets.com/exterior-ballistics/5-6-muzzle-velocity-dependence-on-cartridge-temperature/">Muzzle Velocity Dependence on Cartridge Temperature</a><br />
Section 6.0 <a href="https://www.sierrabullets.com/exterior-ballistics/6-0-equations-of-bullet-flight/">Equations of Bullet Flight</a><br />
Section 6.1 <a href="https://www.sierrabullets.com/exterior-ballistics/6-1-differential-equations-of-bullet-motion/">Differential Equations of Bullet Motion</a><br />
Section 6.2 <a href="https://www.sierrabullets.com/exterior-ballistics/6-2-drag-force-and-the-drag-function/">Drag Force and the Drag Function</a><br />
Section 6.3/Section 6.3.1 <a href="https://www.sierrabullets.com/exterior-ballistics/6-3-siaccis-method-6-3-1-the-change-of-independent-variables/">Siacci&#8217;s Method</a><a href="https://www.sierrabullets.com/exterior-ballistics/6-3-siaccis-method-6-3-1-the-change-of-independent-variables/">/The Change of Independent Variables</a><br />
Section 6.3.2 <a href="https://www.sierrabullets.com/exterior-ballistics/6-3-2-the-assumption/">The Assumption</a><br />
Section 6.4 <a href="https://www.sierrabullets.com/exterior-ballistics/6-4-mayevskis-analytical-form-of-the-drag-mode/">Mayevski&#8217;s Analytical Form of the Drag Model</a><br />
Section 6.5 <a href="https://www.sierrabullets.com/exterior-ballistics/6-5-closed-form-solutions-for-trajectory-parameters/">Closed-Form Solutions for Trajectory Parameters</a><br />
Section 6.6 <a href="https://www.sierrabullets.com/exterior-ballistics/6-6-other-useful-equations/">Other Useful Equations</a><br />
Section 6.6.1 <a href="https://www.sierrabullets.com/exterior-ballistics/6-6-1-references/">References</a></p>
<p></big></p>
<p><a href="https://www.sierrabullets.com/exterior-ballistics/" target="_blank"><img src="http://accurateshooter.net/pix/sierra23ball03.jpg" alt="Sierra Bullets Ballistics Resources"></a></p>
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		<title>How Altitude and Barometric Pressure Affect Projectile Ballistics</title>
		<link>https://bulletin.accurateshooter.com/2022/11/how-altitude-and-barometric-pressure-affect-projectile-ballistics/</link>
		<comments>https://bulletin.accurateshooter.com/2022/11/how-altitude-and-barometric-pressure-affect-projectile-ballistics/#comments</comments>
		<pubDate>Mon, 21 Nov 2022 06:20:05 +0000</pubDate>
		<dc:creator><![CDATA[Editor]]></dc:creator>
				<category><![CDATA[- Articles]]></category>
		<category><![CDATA[Bullets, Brass, Ammo]]></category>
		<category><![CDATA[Tech Tip]]></category>
		<category><![CDATA[Air Pressure]]></category>
		<category><![CDATA[Altitude]]></category>
		<category><![CDATA[ballistics]]></category>
		<category><![CDATA[BC]]></category>
		<category><![CDATA[Coefficient]]></category>
		<category><![CDATA[Density Altitude]]></category>
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		<guid isPermaLink="false">http://bulletin.accurateshooter.com/?p=68296</guid>
		<description><![CDATA[Photo shows the new ZEISS LRP S5 318-50 first focal plane (FFP) scope. &#8220;A bullet launched at a higher altitude is able to fly slightly farther (in the thinner air) for every increment of downward movement. Effectively, the bullet behaves as if it has a higher ballistic coefficient.&#8221; Last month a good friend ventured to [&#8230;]]]></description>
				<content:encoded><![CDATA[<p><img src="https://accurateshooter.net/pix/altitude22x1.jpg" alt="altitude ballistics zeiss LRP S5 318-50 FFP scope"><br />
<i>Photo shows the new <a href="http://www.zeiss.com/lrp-s5" target="_blank">ZEISS LRP S5 318-50</a> first focal plane (FFP) scope.</i></p>
<blockquote><p>&#8220;A bullet launched at a higher altitude is able to fly slightly farther (in the thinner air) for every increment of downward movement. Effectively, the bullet behaves as if it has a higher ballistic coefficient.&#8221;</p></blockquote>
<p><big>Last month a good friend ventured to the high country of Colorado to pursue elk. He recently zeroed his rifle in California, at a range just a few hundred feet Above Mean Sea Level (AMSL). He wondered if the higher altitude in Colorado could alter his ballistics. The answer is a definite yes. However the good news is that <strong>free ballistics calculators</strong> can help you plot reliable drop charts for various shooting locations, high or low.</big></p>
<p><img class="alignright" hspace="12" src="https://accurateshooter.net/Blog/suuntoalt.jpg" alt="Suunto Altimeter">The question has been posed: &#8220;What effect does altitude have on the flight of a bullet?&#8221; The simplistic answer is that, <strong>at higher altitudes, the air is thinner (lower density), so there is less drag</strong> on the bullet. This means that the amount of bullet drop is less at any given flight distance from the muzzle. Since the force of gravity is essentially constant on the earth&#8217;s surface (for practical purposes), the bullet&#8217;s downward acceleration doesn&#8217;t change, but a bullet launched at a higher altitude is able to fly slightly farther (in the thinner air) for every increment of downward movement. Effectively, at higher altitudes, the bullet behaves as if it has a<strong> higher ballistic coefficient</strong>.</p>
<p>Forum member Milanuk explains that the <strong>key factor is not altitude, but rather air pressure</strong>. Milanuk writes:</p>
<blockquote><p><big>&#8220;In basic terms, as your altitude increases, the density of the air the bullet must travel through decreases, thereby reducing the drag on the bullet. Generally, the higher the altitude, the less the bullet will drop. For example, I shoot at a couple ranges here in the Pacific Northwest. Both are at 1000&#8242; AMSL (Above Mean Sea Level) or less. I&#8217;ll need about 29-30 MOA to get from 100 yards to 1000 yards with a Berger 155gr VLD at 2960 fps. By contrast, in Raton, NM, located at 6600&#8242; AMSL, I&#8217;ll only need about 24-25 MOA to do the same. That&#8217;s a significant difference.</p>
<p>Note that <strong>it is the barometric pressure that really matters, not simply the nominal altitude</strong>. The barometric pressure will indicate the reduced pressure from a higher altitude, but it will also show you the pressure changes as a front moves in, etc. which can play havoc w/ your calculated come-ups. Most altimeters are simply barometers that read in feet instead of inches of mercury.&#8221;</big></p></blockquote>
<p>As Milanuk states, it is NOT altitude per se, but the <strong>LOCAL barometric pressure</strong> (sometimes called &#8220;station pressure&#8221;) that is key. The two atmospheric conditions that most effect bullet flight are air temperature, and barometric pressure. Normally, humidity has a negligible effect. It&#8217;s important to remember that the barometric pressure reported on the radio (or internet) may be stated as a sea level equivalency. So in Denver (at 6,000 feet AMSL), if the local pressure is 24&#8243;, the radio will report the barometric pressure to be 30&#8243;. If you do high altitude shooting at long range, <strong>bring along a Kestrel</strong>, or remember to mentally correct the radio station&#8217;s pressure, by 1&#8243; per 1,000 feet.</p>
<blockquote><p><center><b>Trajectory of Bullet fired at Sea Level</b><br />
<img width="500" height="200" src="https://accurateshooter.net/Blog/altitude0x350a.png"></center></p>
<p><center><b>Trajectory of Bullet fired at 20,000 feet</b><br />
<img width="500" height="200" src="http://accurateshooter.net/Blog/altitude20000x350b.png"></center></p>
<p>You can do your own experimental calculations using <a href="https://www.jbmballistics.com/ballistics/calculators/calculators.shtml" target="new">JBM Online Ballistics</a> (free to use). Here is an extreme example, with two printouts (generated with Point Blank software), one showing bullet trajectory at sea level (0&#8242; altitude) and one at 20,000 feet. For demonstration sake, we assigned a low 0.2 BC to the bullet, with a velocity of 3000 fps.</p></blockquote>
<p>To learn more about all aspects of Exterior Ballistics, Hornady has a useful discussion of <a href="https://www.hornady.com/team-hornady/ballistic-calculators/ballistic-resources/external-ballistics" target="new">External Ballistics</a> including the effects of altitude and temperature. To dig deeper, <a href="https://www.sierrabullets.com/exterior-ballistics/" target="_blank">Sierra Bullets</a> has a comprehensive <a href="https://www.sierrabullets.com/exterior-ballistics/" target="_blank">Exterior Ballistics Resource Page</a> with multiple sections from the Sierra Manual (4th and 5th Editions), including:</p>
<p>Section 3.0: <a href="https://www.sierrabullets.com/exterior-ballistics/3-0-exterior-ballistic-effects-on-bullet-flight/" target="_blank">Exterior Ballistic Effects on Bullet Flight</a><br />
Section 3.1: <a href="https://www.sierrabullets.com/exterior-ballistics/3-1-effects-of-altitude-and-atmospheric-conditions/" target="_blank">Effects of Altitude and Atmospheric Conditions</a><br />
Section 3.2: <a href="https://www.sierrabullets.com/exterior-ballistics/3-2-effects-of-winds/" target="_blank">Effects of Wind</a><br />
Section 3.3: <a href="https://www.sierrabullets.com/exterior-ballistics/3-3-effects-of-shooting-uphill-or-downhill/" target="_blank">Effects of Shooting Uphill or Downhill</a></p>
<p>Example from Section 3.0: &#8220;When a bullet flies through the air, two types of forces act on the bullet to determine its path (trajectory) through the air. The first is gravitational force; the other is aerodynamics. Several kinds of aerodynamic forces act on a bullet: drag, lift, side forces, Magnus force, spin damping force, pitch damping force, and Magnus cross force. The most important of these aerodynamic forces is drag. All the others are very small in comparison when the bullet is spin-stabilized.&#8221;</p>
]]></content:encoded>
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		</item>
		<item>
		<title>How Altitude Affects Bullet Ballistics (Drag and Drop)</title>
		<link>https://bulletin.accurateshooter.com/2021/10/how-altitude-affects-bullet-ballistics-drag-and-drop/</link>
		<comments>https://bulletin.accurateshooter.com/2021/10/how-altitude-affects-bullet-ballistics-drag-and-drop/#comments</comments>
		<pubDate>Tue, 19 Oct 2021 14:17:59 +0000</pubDate>
		<dc:creator><![CDATA[Editor]]></dc:creator>
				<category><![CDATA[- Articles]]></category>
		<category><![CDATA[Bullets, Brass, Ammo]]></category>
		<category><![CDATA[Hunting/Varminting]]></category>
		<category><![CDATA[Tech Tip]]></category>
		<category><![CDATA[Air Pressure]]></category>
		<category><![CDATA[Altitude]]></category>
		<category><![CDATA[ballistics]]></category>
		<category><![CDATA[BC]]></category>
		<category><![CDATA[Coefficient]]></category>
		<category><![CDATA[Density Altitude]]></category>
		<category><![CDATA[Kestrel]]></category>
		<category><![CDATA[Trajectory]]></category>

		<guid isPermaLink="false">http://bulletin.accurateshooter.com/?p=66624</guid>
		<description><![CDATA[Photo shows the new ZEISS LRP S5 318-50 first focal plane (FFP) scope. &#8220;A bullet launched at a higher altitude is able to fly slightly farther (in the thinner air) for every increment of downward movement. Effectively, the bullet behaves as if it has a higher ballistic coefficient.&#8221; It&#8217;s hunting season, and a good friend [&#8230;]]]></description>
				<content:encoded><![CDATA[<p><img src="https://accurateshooter.net/pix/altitude21x1.jpg" alt="altitude ballistics zeiss LRP S5 318-50 FFP scope"><br />
<i>Photo shows the new <a href="http://www.zeiss.com/lrp-s5" target="_blank">ZEISS LRP S5 318-50</a> first focal plane (FFP) scope.</i></p>
<blockquote><p>&#8220;A bullet launched at a higher altitude is able to fly slightly farther (in the thinner air) for every increment of downward movement. Effectively, the bullet behaves as if it has a higher ballistic coefficient.&#8221;</p></blockquote>
<p>It&#8217;s hunting season, and a good friend is heading to the high country of Colorado next week to pursue elk. He recently zeroed his rifle in California, at a range just a few hundred feet Above Mean Sea Level (AMSL). He wondered if the higher altitude in Colorado could alter his ballistics. The answer is a definite yes. However the good news is that free ballistics calculators can help you plot reliable drop charts for various shooting locations, high or low.</p>
<p><img class="alignright" hspace="12" src="http://accurateshooter.net/Blog/suuntoalt.jpg" alt="Suunto Altimeter">The question has been posed: &#8220;What effect does altitude have on the flight of a bullet?&#8221; The simplistic answer is that, <strong>at higher altitudes, the air is thinner (lower density), so there is less drag</strong> on the bullet. This means that the amount of bullet drop is less at any given flight distance from the muzzle. Since the force of gravity is essentially constant on the earth&#8217;s surface (for practical purposes), the bullet&#8217;s downward acceleration doesn&#8217;t change, but a bullet launched at a higher altitude is able to fly slightly farther (in the thinner air) for every increment of downward movement. Effectively, at higher altitudes, the bullet behaves as if it has a<strong> higher ballistic coefficient</strong>.</p>
<p>Forum member Milanuk explains that the <strong>key factor is not altitude, but rather air pressure</strong>. Milanuk writes:</p>
<blockquote><p><big>&#8220;In basic terms, as your altitude increases, the density of the air the bullet must travel through decreases, thereby reducing the drag on the bullet. Generally, the higher the altitude, the less the bullet will drop. For example, I shoot at a couple ranges here in the Pacific Northwest. Both are at 1000&#8242; AMSL (Above Mean Sea Level) or less. I&#8217;ll need about 29-30 MOA to get from 100 yards to 1000 yards with a Berger 155gr VLD at 2960 fps. By contrast, in Raton, NM, located at 6600&#8242; AMSL, I&#8217;ll only need about 24-25 MOA to do the same. That&#8217;s a significant difference.</p>
<p>Note that <strong>it is the barometric pressure that really matters, not simply the nominal altitude</strong>. The barometric pressure will indicate the reduced pressure from a higher altitude, but it will also show you the pressure changes as a front moves in, etc. which can play havoc w/ your calculated come-ups. Most altimeters are simply barometers that read in feet instead of inches of mercury.&#8221;</big></p></blockquote>
<p>As Milanuk states, it is NOT altitude per se, but the <strong>LOCAL barometric pressure</strong> (sometimes called &#8220;station pressure&#8221;) that is key. The two atmospheric conditions that most effect bullet flight are air temperature, and barometric pressure. Normally, humidity has a negligible effect. It&#8217;s important to remember that the barometric pressure reported on the radio (or internet) may be stated as a sea level equivalency. So in Denver (at 6,000 feet AMSL), if the local pressure is 24&#8243;, the radio will report the barometric pressure to be 30&#8243;. If you do high altitude shooting at long range, <strong>bring along a Kestrel</strong>, or remember to mentally correct the radio station&#8217;s pressure, by 1&#8243; per 1,000 feet.</p>
<blockquote><p><center><b>Trajectory of Bullet fired at Sea Level</b><br />
<img width="500" height="200" src="http://accurateshooter.net/Blog/altitude0x350a.png"></center></p>
<p><center><b>Trajectory of Bullet fired at 20,000 feet</b><br />
<img width="500" height="200" src="http://accurateshooter.net/Blog/altitude20000x350b.png"></center></p>
<p>You can do your own experimental calculations using <a href="http://www.jbmballistics.com/ballistics/calculators/calculators.shtml" target="new">JBM Online Ballistics</a> (free to use). Here is an extreme example, with two printouts (generated with Point Blank software), one showing bullet trajectory at sea level (0&#8242; altitude) and one at 20,000 feet. For demonstration sake, we assigned a low 0.2 BC to the bullet, with a velocity of 3000 fps.</p></blockquote>
<p>To learn more about all aspects of Exterior Ballistics, Hornady has a useful discussion of <a href="https://www.hornady.com/team-hornady/ballistic-calculators/ballistic-resources/external-ballistics" target="new">External Ballistics</a> including the effects of altitude and temperature. To dig deeper, <a href="https://www.sierrabullets.com/exterior-ballistics/" target="_blank">Sierra Bullets</a> has a comprehensive <a href="https://www.sierrabullets.com/exterior-ballistics/" target="_blank">Exterior Ballistics Resource Page</a> with multiple sections from the Sierra Manual (4th and 5th Editions), including:</p>
<p>Section 3.0: <a href="https://www.sierrabullets.com/exterior-ballistics/3-0-exterior-ballistic-effects-on-bullet-flight/" target="_blank">Exterior Ballistic Effects on Bullet Flight</a><br />
Section 3.1: <a href="https://www.sierrabullets.com/exterior-ballistics/3-1-effects-of-altitude-and-atmospheric-conditions/" target="_blank">Effects of Altitude and Atmospheric Conditions</a><br />
Section 3.2: <a href="https://www.sierrabullets.com/exterior-ballistics/3-2-effects-of-winds/" target="_blank">Effects of Wind</a><br />
Section 3.3: <a href="https://www.sierrabullets.com/exterior-ballistics/3-3-effects-of-shooting-uphill-or-downhill/" target="_blank">Effects of Shooting Uphill or Downhill</a></p>
<p>Example from Section 3.0: &#8220;When a bullet flies through the air, two types of forces act on the bullet to determine its path (trajectory) through the air. The first is gravitational force; the other is aerodynamics. Several kinds of aerodynamic forces act on a bullet: drag, lift, side forces, Magnus force, spin damping force, pitch damping force, and Magnus cross force. The most important of these aerodynamic forces is drag. All the others are very small in comparison when the bullet is spin-stabilized.&#8221;</p>
]]></content:encoded>
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		</item>
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		<title>Ballistics TIP: How Altitude and Air Pressure Affect Bullet Flight</title>
		<link>https://bulletin.accurateshooter.com/2019/08/ballistics-tip-how-alltitude-and-air-pressure-affect-bullet-flight/</link>
		<comments>https://bulletin.accurateshooter.com/2019/08/ballistics-tip-how-alltitude-and-air-pressure-affect-bullet-flight/#comments</comments>
		<pubDate>Thu, 01 Aug 2019 08:00:16 +0000</pubDate>
		<dc:creator><![CDATA[Editor]]></dc:creator>
				<category><![CDATA[Bullets, Brass, Ammo]]></category>
		<category><![CDATA[Tech Tip]]></category>
		<category><![CDATA[Air Pressure]]></category>
		<category><![CDATA[Altitude]]></category>
		<category><![CDATA[ballistics]]></category>
		<category><![CDATA[BC]]></category>
		<category><![CDATA[Coefficient]]></category>
		<category><![CDATA[Density Altitude]]></category>
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		<category><![CDATA[Trajectory]]></category>

		<guid isPermaLink="false">http://bulletin.accurateshooter.com/?p=61545</guid>
		<description><![CDATA[Trajectory of Bullet fired at Sea Level Trajectory of Bullet fired at 20,000 feet You can do your own experimental calculations using JBM Online Ballistics (free to use). Here is an extreme example, with two printouts (generated with Point Blank software), one showing bullet trajectory at sea level (0&#8242; altitude) and one at 20,000 feet. [&#8230;]]]></description>
				<content:encoded><![CDATA[<blockquote><p><center><b>Trajectory of Bullet fired at Sea Level</b><br />
<img width="500" height="200" src="http://accurateshooter.net/Blog/altitude0x350a.png"></center></p>
<p><center><b>Trajectory of Bullet fired at 20,000 feet</b><br />
<img width="500" height="200" src="http://accurateshooter.net/Blog/altitude20000x350b.png"></center></p>
<p>You can do your own experimental calculations using <a href="http://www.jbmballistics.com/ballistics/calculators/calculators.shtml" target="new">JBM Online Ballistics</a> (free to use). Here is an extreme example, with two printouts (generated with Point Blank software), one showing bullet trajectory at sea level (0&#8242; altitude) and one at 20,000 feet. For demonstration sake, we assigned a low 0.2 BC to the bullet, with a velocity of 3000 fps.</p></blockquote>
<p><img align="right" hspace="6" src="http://accurateshooter.net/Blog/suuntoalt.jpg" alt="Suunto Altimeter">One of our readers asked &#8220;What effect does altitude have on the flight of a bullet?&#8221; The simplistic answer is that, <strong>at higher altitudes, the air is thinner (lower density), so there is less drag</strong> on the bullet. This means that the amount of bullet drop is less at any given flight distance from the muzzle. Since the force of gravity is essentially constant on the earth&#8217;s surface (for practical purposes), the bullet&#8217;s downward acceleration doesn&#8217;t change, but a bullet launched at a higher altitude is able to fly slightly farther (in the thinner air) for every increment of downward movement. Effectively, the bullet behaves as if it has a higher ballistic coefficient.</p>
<p>Forum member Milanuk explains that the <strong>key factor is not altitude, but rather air pressure</strong>. Milanuk writes:</p>
<p>&#8220;In basic terms, as your altitude increases, the density of the air the bullet must travel through decreases, thereby reducing the drag on the bullet. Generally, the higher the altitude, the less the bullet will drop. For example, I shoot at a couple ranges here in the Pacific Northwest. Both are at 1000&#8242; ASL or less. I&#8217;ll need about 29-30 MOA to get from 100 yard to 1000 yards with a Berger 155gr VLD @ 2960fps. By contrast, in Raton, NM, located at 6600&#8242; ASL, I&#8217;ll only need about 24-25 MOA to do the same. That&#8217;s a significant difference.</p>
<p>Note that <strong>it is the barometric pressure that really matters, not simply the nominal altitude</strong>. The barometric pressure will indicate the reduced pressure from a higher altitude, but it will also show you the pressure changes as a front moves in, etc. which can play havoc w/ your calculated come-ups. Most altimeters are simply barometers that read in feet instead of inches of mercury.&#8221;</p>
<p>As Milanuk states, it is NOT altitude per se, but the LOCAL barometric pressure (sometimes called &#8220;station pressure&#8221;) that is key. The two atmospheric conditions that most effect bullet flight are air temperature, and barometric pressure. Normally, humidity has a negligible effect.</p>
<p>It&#8217;s important to remember that the barometric pressure reported on the radio (or internet) may be stated as a sea level equivalency. So in Denver (at 6,000 feet amsl), if the local pressure is 24&#8243;, the radio will report the barometric pressure to be 30&#8243;. If you do high altitude shooting at long range, bring along a Kestrel, or remember to mentally correct the radio station&#8217;s pressure, by 1&#8243; per 1,000 feet.&#8221;</p>
<p>If you want to learn more about all aspects of <a href="http://www.exteriorballistics.com/ebexplained/index.cfm" target="new">External Ballistics</a>, <a href="http://www.exteriorballistics.com/index.cfm" target="new">ExteriorBallistics.com</a> provides a variety of useful resources. In particular, on that site, Section 3.1 of the Sierra Manual is reprinted, covering <a href="http://www.exteriorballistics.com/ebexplained/5th/31.cfm" target="new">Effects of Altitude and Atmospheric Pressure</a> on bullet flight. </p>
]]></content:encoded>
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		</item>
		<item>
		<title>Altitude, Air Pressure and Ballistics &#8212; What You Need to Know</title>
		<link>https://bulletin.accurateshooter.com/2016/11/altitude-air-pressure-and-ballistics-what-you-need-to-know/</link>
		<comments>https://bulletin.accurateshooter.com/2016/11/altitude-air-pressure-and-ballistics-what-you-need-to-know/#comments</comments>
		<pubDate>Tue, 15 Nov 2016 16:00:13 +0000</pubDate>
		<dc:creator><![CDATA[Editor]]></dc:creator>
				<category><![CDATA[- Articles]]></category>
		<category><![CDATA[Bullets, Brass, Ammo]]></category>
		<category><![CDATA[Air Pressure]]></category>
		<category><![CDATA[Altitude]]></category>
		<category><![CDATA[ballistics]]></category>
		<category><![CDATA[Density Altitude]]></category>
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		<category><![CDATA[Milanuk]]></category>

		<guid isPermaLink="false">http://bulletin.accurateshooter.com/?p=58906</guid>
		<description><![CDATA[Trajectory of Bullet fired at Sea Level Trajectory of Bullet fired at 20,000 feet You can do your own experimental calculations using JBM Online Ballistics (free to use). Here is an extreme example, with two printouts (generated with Point Blank software), one showing bullet trajectory at sea level (0&#8242; altitude) and one at 20,000 feet. [&#8230;]]]></description>
				<content:encoded><![CDATA[<blockquote><p><center><b>Trajectory of Bullet fired at Sea Level</b><br />
<img width="500" height="200" src="http://accurateshooter.net/Blog/altitude0x350a.png"></center></p>
<p><center><b>Trajectory of Bullet fired at 20,000 feet</b><br />
<img width="500" height="200" src="http://accurateshooter.net/Blog/altitude20000x350b.png"></center></p>
<p>You can do your own experimental calculations using <a href="http://www.jbmballistics.com/ballistics/calculators/calculators.shtml" target="new">JBM Online Ballistics</a> (free to use). Here is an extreme example, with two printouts (generated with Point Blank software), one showing bullet trajectory at sea level (0&#8242; altitude) and one at 20,000 feet. For demonstration sake, we assigned a low 0.2 BC to the bullet, with a velocity of 3000 fps.</p></blockquote>
<p><img align="right" hspace="6" src="http://accurateshooter.net/Blog/suuntoalt.jpg" alt="Suunto Altimeter">One of our readers asked &#8220;What effect does altitude have on the flight of a bullet?&#8221; The simplistic answer is that, <strong>at higher altitudes, the air is thinner (lower density), so there is less drag</strong> on the bullet. This means that the amount of bullet drop is less at any given flight distance from the muzzle. Since the force of gravity is essentially constant on the earth&#8217;s surface (for practical purposes), the bullet&#8217;s downward acceleration doesn&#8217;t change, but a bullet launched at a higher altitude is able to fly slightly farther (in the thinner air) for every increment of downward movement. Effectively, the bullet behaves as if it has a higher ballistic coefficient.</p>
<p>Forum member Milanuk explains that the <strong>key factor is not altitude, but rather air pressure</strong>. Milanuk writes:</p>
<p>&#8220;In basic terms, as your altitude increases, the density of the air the bullet must travel through decreases, thereby reducing the drag on the bullet. Generally, the higher the altitude, the less the bullet will drop. For example, I shoot at a couple ranges here in the Pacific Northwest. Both are at 1000&#8242; ASL or less. I&#8217;ll need about 29-30 MOA to get from 100 yard to 1000 yards with a Berger 155gr VLD @ 2960fps. By contrast, in Raton, NM, located at 6600&#8242; ASL, I&#8217;ll only need about 24-25 MOA to do the same. That&#8217;s a significant difference.</p>
<p>Note that <strong>it is the barometric pressure that really matters, not simply the nominal altitude</strong>. The barometric pressure will indicate the reduced pressure from a higher altitude, but it will also show you the pressure changes as a front moves in, etc. which can play havoc w/ your calculated come-ups. Most altimeters are simply barometers that read in feet instead of inches of mercury.&#8221;</p>
<p>As Milanuk states, it is NOT altitude per se, but the LOCAL barometric pressure (sometimes called &#8220;station pressure&#8221;) that is key. The two atmospheric conditions that most effect bullet flight are air temperature, and barometric pressure. Normally, humidity has a negligible effect.</p>
<p>It&#8217;s important to remember that the barometric pressure reported on the radio (or internet) may be stated as a sea level equivalency. So in Denver (at 6,000 feet amsl), if the local pressure is 24&#8243;, the radio will report the barometric pressure to be 30&#8243;. If you do high altitude shooting at long range, bring along a Kestrel, or remember to mentally correct the radio station&#8217;s pressure, by 1&#8243; per 1,000 feet.&#8221;</p>
<p>If you want to learn more about all aspects of <a href="http://www.exteriorballistics.com/ebexplained/index.cfm" target="new">External Ballistics</a>, <a href="http://www.exteriorballistics.com/index.cfm" target="new">ExteriorBallistics.com</a> provides a variety of useful resources. In particular, on that site, Section 3.1 of the Sierra Manual is reprinted, covering <a href="http://www.exteriorballistics.com/ebexplained/5th/31.cfm" target="new">Effects of Altitude and Atmospheric Pressure</a> on bullet flight. </p>
]]></content:encoded>
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		<title>FREE Ballistics Program from Berger Bullets</title>
		<link>https://bulletin.accurateshooter.com/2011/02/free-ballistics-program-from-berger-bullets/</link>
		<comments>https://bulletin.accurateshooter.com/2011/02/free-ballistics-program-from-berger-bullets/#comments</comments>
		<pubDate>Sun, 20 Feb 2011 19:52:12 +0000</pubDate>
		<dc:creator><![CDATA[Editor]]></dc:creator>
				<category><![CDATA[Bullets, Brass, Ammo]]></category>
		<category><![CDATA[New Product]]></category>
		<category><![CDATA[Altitude]]></category>
		<category><![CDATA[ballistics]]></category>
		<category><![CDATA[Berger]]></category>
		<category><![CDATA[Bryan Litz]]></category>
		<category><![CDATA[G1]]></category>
		<category><![CDATA[G7]]></category>
		<category><![CDATA[Velocity]]></category>

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		<description><![CDATA[There&#8217;s a lot of buzz about ballistics programs for smartphones. Those are handy, to be sure, but most people still need a solid, full-featured program to run on their home computers. Berger Bullets offers a sophisticated ballistics programs for MS Windows computers that works really well, and lets you print out results. Up-to-Date G7 BCs [&#8230;]]]></description>
				<content:encoded><![CDATA[<p><a href="http://www.bergerbullets.com/Ballistics%20Program/BergerBallistics(11).exe" target="new"><img class="alignright" src="http://accurateshooter.net/Blog/bergerprogram01.gif" alt="Berger Ballistics Program" hspace="6" align="right" /></a>There&#8217;s a lot of buzz about ballistics programs for smartphones. Those are handy, to be sure, but most people still need a solid, full-featured program to run on their home computers. <a href="http://www.bergerbullets.com/Ballistics%20Program/index.html" target="new">Berger Bullets</a> offers a sophisticated ballistics programs for MS Windows computers that works really well, and lets you print out results. Up-to-Date G7 BCs for Berger projectiles are built-in to the program, and the price is right &#8212; FREE.</p>
<p><a href="http://www.bergerbullets.com/Ballistics%20Program/BergerBallistics(11).exe" target="new"><strong>CLICK HERE to Download Berger Ballistics Program</strong></a></p>
<p>The program is basic enough to be easy to use, but flexible enough to allow you to calculate custom ballistics for your rifle and load. The program accounts for all the basic external ballistic parameters including bullet BC and muzzle velocity, atmospherics, uphill/downhill shooting, etc. The output tabulates velocity, energy and time of flight as a function of range. Bullet path and wind deflection are displayed in your choice of inches, centimeters, MOA or MILS.</p>
<p><img class="alignright" src="http://accurateshooter.net/Blog/bergerprogram02.gif" alt="" hspace="6" align="right" /><strong>Instructions for Program</strong><br />
On the <a href="http://02b0516.netsolhost.com/blog1/?p=99" target="new">Berger Bullets Blog</a> (1/26/2010), You&#8217;ll find a description of program features and a complete set of instructions. Here are instructions for the bullet variables: &#8220;The bullet inputs are straightforward. The BC can be entered in reference to either the G1 or G7 standard. You can find the G1 or G7 BC for your bullet either printed on the bullet box label, or on our products page. For accurate results, you should measure the muzzle velocity with a good chronograph. If you don’t have access to a chronograph, you can estimate the muzzle velocity based on your load data.&#8221;</p>
<blockquote><p><strong>Tips for Best Results</strong><br />
Bryan Litz includes tips on getting the most from the Berger Ballistics program. Some of Bryan&#8217;s suggestions will also help you when working with other ballistics software:</p>
<p><strong>G1 vs. G7 BC:</strong> The accuracy of the ballistic solution is only as accurate as the inputs you give it. The advertised BCs for Berger bullets are established by actual field firing tests over long range and are very accurate. Using the properly referenced BC (G7 vs. G1) for the bullet you’re modeling is important. For any bullet with a boat tail, we recommend using the G7 BC.</p>
<p><strong>Muzzle Velocity:</strong> Knowing your true muzzle velocity is important when calculating external ballistics. It’s best to measure your muzzle velocity directly with a chronograph.</p>
<p><strong>Altitude and Atmosphere:</strong> If you want a truly accurate long-range trajectory prediction, you can’t ignore atmospheric effects. This is especially true the farther you get from standard conditions (sea level altitude, 59 degrees Fahrenheit, 0% humidity).</p>
<p><strong>Scope Verification:</strong> It’s important to verify the most important link between the calculated ballistics and your point of impact: your scope. If the ballistics program calculates 30.0 MOA of drop for a particular shot, and you dial your scope to 30.0 MOA, are you sure it&#8217;s giving you exactly 30.0 MOA? In reality, many scopes have enough error in them to cause misses at long range. It’s important to verify the value of your scope clicks by firing groups at short range.</p></blockquote>
<p>If you have further questions not answered on <a href="http://02b0516.netsolhost.com/blog1/?p=99" target="new">Berger&#8217;s Blog Page</a>, email Bryan.Litz [at] bergerbullets.com. NOTE: If your computer won’t run the program, please download and install this Java update: <a href="http://www.java.com/en/download/index.jsp" target="new">http://www.java.com/en/download/index.jsp</a>. This is a Windows PC program. You may have problems trying to run it on a MAC in emulation.</p>
<address>Story sourced by Edlongrange.</address>
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