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October 23rd, 2012
Put the same load in a variety of barrels (with the same length and chamberings) and you’ll see a wide variance in muzzle velocity. In fact, it’s not unusual to see up to 100 fps difference from one barrel to the next. We demonstrated this with a comparison test of Lapua factory ammo.
Chron Testing Lapua Factory Ammo
At our Southern California test range, we chronographed Lapua 105gr 6mmBR factory ammo in three different 8-twist barrels of similar length. The results were fascinating. Lapua specs this ammo at 2790 fps, based on Lapua’s testing with its own 26″ test barrel. We observed a speed variance of 67 fps based on tests with three aftermarket barrels.
Brand ‘S’ and Brand ‘PN’ were pre-fit barrels shot on Savage actions. Brand ‘K’ was fitted to a custom action. All test barrels were throated for the 100-108 grain bullets, though there may have been some slight variances in barrel freebore. With a COAL of 2.330″, the rounds were “jumping” to the rifling in all barrels. Among the four barrels, Brand ‘PN’ was the fastest at 2824 fps average — 67 fps faster than the slowest barrel. Roughly 10 fps can be attributed to the slightly longer length (27″ vs. 26″), but otherwise this particular barrel was simply faster than the rest. (Click Here for results of 6mmBR Barrel Length Velocity Test).
Results Are Barrel-Specific, Not Brand-Specific
These tests demonstrate that the exact same load can perform very differently in different barrels. We aren’t publishing the barrel-makers’ names, because it would be wrong to assume that ‘Brand X’ is always going to be faster than ‘Brand Y’ based on test results from a single barrel. In fact, velocities can vary up to 100 fps with two identical-spec barrels from the SAME manufacturer. That’s right, you can have two 8-twist, 26″ barrels, with the same land-groove configuration and contour, from the same manufacturer, and one can be much faster than another.
Don’t Demand More Than Your Barrel Can Deliver
We often hear guys lament, “I don’t get it… how can you guys get 2900 fps with your 6BRs and I can only get 2840?” The answer may simply be that the barrel is slower than average. If you have a slow barrel, you can try using more powder, but there is a good chance it may never run as fast as an inherently fast barrel. You shouldn’t knock yourself out (and over-stress your brass) trying to duplicate the velocities someone else may be getting. You need to work within the limits of your barrel.
Factory Ammo Provides a Benchmark
 If you have a .223 Rem, 6BR, .243 Win, 6.5×47 Lapua, 6.5×55, .308 Win, 30-06, or 300 WM Rifle, we recommend you buy a box of Lapua factory-loaded ammo. This stuff will shoot great (typically around half-MOA), and it can give you a baseline to determine how your barrel stacks up speedwise. When you complete a new 6BR rifle, it’s wise to get a box of the factory ammo and chronograph it. That will immediately give you a good idea whether you have a slow, average, or fast barrel. Then you can set your velocity goals accordingly. For example, if the factory 6BR ammo runs about 2780-2790 fps in your gun, it has an average barrel. If it runs 2820+ in a 26″ barrel (or 2835 fps in a 28″), you’ve got a fast tube.
August 20th, 2012
Here’s good news for owners of Shooting Chrony Chronographs — you can purchase a Chrony LED Lamp (CLL) upgrade kit that allows your Chrony to work indoors. In addition, the new LED illuminators will enhance outdoor performance in uneven or shaded lighting conditions. The CLL kit costs $87.95 and can be ordered directly from the Shooting Chrony Website, or from vendors such as MidwayUSA.com.
Why the LED Illuminator Kit Is Needed
Shooting Chronys are popular “entry-level” chronographs. They are inexpensive to purchase and they stow compactly with their signature “folding box” design. This Editor used a Shooting Chrony (Beta Master model) for a few years with generally good results. However, I quickly learned that the Shooting Chrony gave the most reliable readings in diffuse mid-morning light with mildly overcast skies (thin cloud layer). The unit did not like to work in the late afternoon with the sun at a low angle. Likewise, uneven, shady conditions caused problems. In summertime, the ultra-bright, noontime summer sun, directly overhead, seemed to “over-power” the diffusers, causing errors. So, I learned to do my speed tests only when conditions were most favorable for the Shooting Chrony. Now, admittedly, not all Shooting Chronys are so temperamental — I’ve seen a few that worked great in bright overhead sunlight. But most Shooting Chronys do seem to struggle with shady conditions or low-angle sunlight.
LED Lamp Kit Components and Accessories
To improve Shooting Chrony reliability in all light conditions, Shooting Chrony offers a $87.95 LED kit (Item #110) that comes with LED-equipped 14″ white diffusers mounted on 16″ wire support rods. The LEDs provide a constant, consistent light source, so you can shoot in the late afternoon and evenings. The kit includes a 120V/220V AC Adapter, output 12VDC @500mA. If AC power is not available, you can run the LED Lamp with an optional 12v dc “Power Station” battery pack (Item #111, $47.95), or you can draw 12v current through an available cigarette lighter-style adapter (Item #112, $10.00).
LED Kit Users Say It Works
We haven’t tested the LED kit ourselves yet, but here’s what one kit buyer had to say:
“If you shot in poor light, you are going to miss velocities no matter what chronograph you are using. You go to all the work of assembling your handloads, set up the chronograph, and then shoot at the target through the detectors… only to get ‘Err 2′ or ‘Err 9′ and use up most or all of the carefully assembled handloads without getting any velocity data. The Chrony LED Lamp assembly has been perfect. Bright sun/no clouds, hazy/cloudy, or shadows/shade makes no difference — all the readings come through without a single ‘Err X’ code. Current draw is also surprisingly low. With the C.L.L. on for five straight hours, the battery pack still shows a full charge.”
February 20th, 2011
 There’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 for Berger projectiles are built-in to the program, and the price is right — FREE.
CLICK HERE to Download Berger Ballistics Program
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.
 Instructions for Program
On the Berger Bullets Blog (1/26/2010), You’ll find a description of program features and a complete set of instructions. Here are instructions for the bullet variables: “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.”
Tips for Best Results
Bryan Litz includes tips on getting the most from the Berger Ballistics program. Some of Bryan’s suggestions will also help you when working with other ballistics software:
G1 vs. G7 BC: 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.
Muzzle Velocity: Knowing your true muzzle velocity is important when calculating external ballistics. It’s best to measure your muzzle velocity directly with a chronograph.
Altitude and Atmosphere: 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).
Scope Verification: 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’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.
If you have further questions not answered on Berger’s Blog Page, email Bryan.Litz [at] bergerbullets.com. NOTE: If your computer won’t run the program, please download and install this Java update: http://www.java.com/en/download/index.jsp. This is a Windows PC program. You may have problems trying to run it on a MAC in emulation.
Story sourced by Edlongrange.
December 15th, 2010
Many folks have been anxiously awaiting the release of Hodgdon’s new Superformance and LeveRevolution powders, high-velocity blended propellants originally developed by Hornady. For select cartridge types, Hornady claims, these new blended spherical powders can deliver 80 to 150 FPS more velocity than other powders on the market.
 Well wait no more — Superformance and LeveRevolution powders are both IN STOCK at Grafs.com now. Both 1-lb and 8-lb containers are in stock. If you’ve been wanting to experiment with either of these new powders — get yours before it’s gone. Supplies are limited.
Here are the options:
Superformance 1LB, Item # HDHSP1, Price: $21.99
Superformance 8LBs, Item # HDHSP8, Price:$153.99
LEVERevolution 1LB, Item # HDHLR1, Price: $21.99
LEVERevolution 8LBs, Item # HDHLR8, Price: $153.99
August 15th, 2009
 If you want to win shooting matches you’ll need to gauge wind speed and direction. While many shooters use the excellent Kestrel line of pocket Weather Trackers, many top shooters are turning to the Windtronic 2, a German-made unit that measures wind speeds from any direction.
The Windtronic features rotating cups mounted on a vertical axis. With this design you don’t have to align the unit with the wind, unlike the Kestrel WindMeter or SpeedTech WindMate™ devices. Many users feel the Windtronic’s unique design allows it to read wind speeds more accurately; it certainly can respond to shifting winds more easily. The omni-directional functionality of the Windtronic allows it to be mounted on a stand or tripod and continuously display current wind speed, max wind speed, and average velocity.
The Windtronic 2 doesn’t guage temperature, barometric pressure, humidity, or density altitude, unlike the more advanced (and expensive) Kestrel 4000/4500 model pocket weather trackers. The Windtronic only records wind speeds, but it does that one task exceptionally well.
Made in Germany by Kaindl Electronics, the Windtronic 2 comes with a 2-year manufacturers warranty and normally retails for $99.00 on Amazon.com. Other dealers include Windtronic.us and Windpowersports.com.
May 6th, 2009
You may have heard rumors about a new 100gr projectile from Berger Bullets. Eric Stecker, Berger’s Master Bulletsmith, confirmed that there will be not one but TWO new 100gr match bullets coming soon from Berger, one in 6mm and one in 6.5mm. These are both boat-tail designs using J4 jackets. Eric explains: “Both these bullets are based on Berger’s proven designs, with standard length ogives and 9° boat-tails. Nothing radical. They are built in response to shooters’ requests to expand our bullet line-up to include new weight options in 6mm and 6.5mm.”
New 100gr 6.5mm Bullet for High Power
Berger’s new 6.5mm 100gr BT Target projectile provides a low-recoil, lighter-weight option for target rifle shooters using the 6.5×47 Lapua, 6.5 Creedmoor, 260 Rem, and 6.5-284 cartridges. The new 6.5mm 100-grainer was created in response to requests from High Power and Across-the-Course shooters for a lighter-recoiling, accurate boat-tail bullet for “short line” work. We predict this bullet may also work well for varmint and small-game hunters. This bullet features a short boat-tail and a “mildly secant” design which should work well either seated into the lands or jumped away from the lands. Bryan Litz says: “it’s definitely not a VLD, but it has a different ogive curve than a typical tangent-ogive bullet.” The shorter length of the 100gr bullet, compared to 140gr-class 6.5mm bullets, should also allow tactical shooters to easily load their ammo to mag length. The calculated BC of the new bullet is 0.370, significantly higher than flat-based 100gr 6.5mm bullets from other manufacturers. A minimum twist rate of 1:10” is recommended for Berger’s hew 6.5mm 100gr Target Bullet.
New 100gr 6mm Match Bullet — More Velocity Than 105/108
Long-range benchresters have had great success with the Berger 108gr match bullet, introduced in 2007. Given the popularity of its tangent-ogive 108, Berger has been developing a shorter, lighter version, which can shoot faster than the 108 in small cartridges such as the 6mmBR, 6mmAR (6-6.5 Grendel), and 6 PPC. The new 6mm 100-grainer will be very similar to the 108. The 100 has the same ogive curve and boat-tail as the 108 but has a shorter OAL and shorter bearing surface (0.368″ vs. 0.409″). A minimum twist rate of 1:8” is recommended for the new 100 — same as for the 108. In a 6BR rifle, the 100-grainer’s reduced bearing surface, combined with reduced mass, should enable Berger’s new 100gr 6mm bullet to fly 50-70 fps faster than the 108 (with charges of equal pressure).
However, there is a trade-off. Being shorter and lighter, the 100-grainer has a lower BC compared to its 108gr big brother. While the Berger 108 has a 0.511 BC, the calculated BC for the 100-grainer is 0.475. That BC difference will show up at long range, but the extra speed of the lighter bullet may enable it to reach a higher, optimal “velocity node” which may deliver superior accuracy in some rifles. We will be testing the new 100-grainer soon. In a 6BR that might max out at 2850 fps with the 108s, we predict the 100gr Berger should run close to 2900 fps. In a 6BR that delivers 2900 fps currently with the 108s, you may see 2950 fps (or more) with the new Berger 100s. The 2900-2950 fps speed range is a well-known “accuracy node” for both 6mm and 6.5mm bullets.
July 19th, 2008
Alliant’s new Reloder 17 powder is the new “Speed King” in its burn-rate category. It promises to raise the velocity bar in many cartridges which work best with slow-burning propellants. Based on initial test results, if you’re using H4350, IMR4350, Reloader 19, Norma URP, or H4831 currently, you may find that RL17 can deliver dramatically higher velocities than other powders. CLICK HERE for FULL REPORT.
RL17 Boosts Speeds by 200 fps
The day after two pounds of RL17 arrived in Phoenix, German Salazar and Bob Jensen tried the new propellant in 6XC and .308 rifles, using an Oehler 43 chronograph equipped with pressure-testing equipment. The results were eye-opening. German was able to get 3311 fps using 107gr Sierra MKs in the 6XC. That’s roughly 200 fps faster than other popular extruded powders can deliver. With the 115 Berger, the 6XC topped 3200 fps, again a very impressive speed gain. Most 6XC shooters find that 3000-3050 fps is the most they can get with a 115gr bullet.
Speed by Design
What’s the secret to this new powder? First it’s made differently than most other propellants. Most extruded powders have an external coating on the kernels that governs burn rate. With RL17, the burn regulating compound saturates the entire kernel — it’s not just on the outside. The practical effect is that RL17 is able to maintain a higher energy level for a longer time — the energy output does not fall off as steeply as other powders. The other factor is density. Reloder 17 has fairly small kernels so it packs very tightly compared to H4831sc. As a result you can fit more powder (by weight) into the case.
Accuracy Testing Comes Next
German will continue his testing with other calibers — as soon as we can get more RL17 from Alliant. German also plans to start accuracy testing next week. If RL17 can deliver accuracy to match its high velocities, it looks like it would be a very good choice for the 6-6.5×47 Lapua, 6XC, 243 Win, 6mm Remington, .284 Winchester, and 30-caliber cartridges with the big (185+ grain) bullets.
Limited reloading data is available currently, but Alliant has distributed a preliminary load data sheet with loads for a dozen popular calibers. CLICK HERE to DOWNLOAD RELODER 17 DATA.
June 13th, 2008
Put the same load in a variety of barrels (with the same length and chamberings) and you’ll see a wide variance in muzzle velocity. In fact, it’s not unusual to see up to 100 fps difference from one barrel to the next. We demonstrated this with a comparison test of Lapua factory ammo.
Chron Testing Lapua Factory Ammo
We recently chronographed Lapua 105gr 6mmBR factory ammo in three different 8-twist barrels of similar length. The results were fascinating. Lapua specs this ammo at 2790 fps, based on Lapua’s testing with its own 26″ test barrel. We observed a speed variance of 67 fps based on tests with three aftermarket barrels.
Brand ‘S’ and Brand ‘PN’ were pre-fit barrels shot on Savage actions. Brand ‘K’ was fitted to a custom action. All test barrels were throated for the 100-108 grain bullets, though there may have been some slight variances in barrel freebore. With a COAL of 2.330″, the rounds were “jumping” to the rifling in all barrels. Among the four barrels, Brand ‘PN’ was the fastest at 2824 fps average — 67 fps faster than the slowest barrel. Roughly 10 fps can be attributed to the slightly longer length (27″ vs. 26″), but otherwise this particular barrel was simply faster than the rest.
Results Are Barrel-Specific, Not Brand-Specific
These tests demonstrate that the exact same load can perform very differently in different barrels. We aren’t publishing the barrel-makers’ names, because it would be wrong to assume that ‘Brand X’ is always going to be faster than ‘Brand Y’ based on test results from a single barrel. In fact, velocities can vary up to 100 fps with two identical-spec barrels from the SAME manufacturer. That’s right, you can have two 8-twist, 26″ barrels, with the same land-groove configuration and contour, from the same manufacturer, and one can be much faster than another.
Don’t Demand More Than Your Barrel Can Deliver
We often hear guys lament, “I don’t get it… how can you guys get 2900 fps with your 6BRs and I can only get 2840?” The answer may simply be that the barrel is slower than average. If you have a slow barrel, you can try using more powder, but there is a good chance it may never run as fast as an inherently fast barrel. You shouldn’t knock yourself out (and over-stress your brass) trying to duplicate the velocities someone else may be getting. You need to work within the limits of your barrel.
Factory Ammo Provides a Benchmark
If you have a .223 Rem, 6BR, .243 Win, 6.5×47 Lapua, 6.5×55, .308 Win, 30-06, or 300 WM Rifle, we recommend you buy a box of Lapua factory-loaded ammo. This stuff will shoot great (typically around half-MOA), and it can give you a baseline to determine how your barrel stacks up speedwise. When you complete a new 6BR rifle, it’s wise to get a box of the factory ammo and chronograph it. That will immediately give you a good idea whether you have a slow, average, or fast barrel. Then you can set your velocity goals accordingly. For example, if the factory 6BR ammo runs about 2780-2790 fps in your gun, it has an average barrel. If it runs 2820+ in a 26″ barrel (or 2835 fps in a 28″), you’ve got a fast tube.
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