This USAMU article explores three different “Philosophies” of precision reloading. Some handloaders seek to produce ammo that yields the very tightest groups (without factoring in the wind). Other shooters load their ammo to deliver the highest safe velocity. That’s because a projectile launched at higher velocity will drift less in the wind. The theory is that even if fast ammo doesn’t produce the tightest groups in zero wind conditions, it will yield higher scores in a the real world (where the wind blows). Lastly, some handloaders favor ammo that is ultra-consistent across a wide temperature range. This last philosophy dictates selection of a powder that is temp-insensitive, even if it may not produce the very best raw accuracy (or speed).
What’s Your Handloading Philosophy?
Objectives of Reloading — Accuracy, Velocity, Temp Stability What do you, the reader, primarily value in your handloads?
Viewpoint ONE: Accuracy Trumps Everything
Some shooters prize consistent, excellent medium/long range accuracy enough that they’re willing to give up some extra velocity (and reduced wind deflection) to obtain that. Their underlying philosophy could be stated: “Superior accuracy is present for every shot, but the wind isn’t”. One’s ability to hold well, aim well and read the wind are all factors in making this type decision. The photo below shows stellar raw accuracy. This is an 0.67″, 10-shot group at 300-yards fired from a text fixture. The group measures just 0.67″. (This shows the USAMU’s 600-yard load with 75gr bullets).
Viewpoint TWO: Load to Highest Safe Velocity for Less Wind Drift
Some shooters value obtaining the highest safe velocity, even if one’s pure, consistent mechanical accuracy at medium/long range isn’t quite as brilliant. The theory here seems to be that a really good hold extracts as much mechanical accuracy from the rifle/ammo as possible, and faster bullets equal occasional “bonus” points snatched from the jaws of wind.
[For example] one of the USAMU’s many Service Rifle National Champions revealed his philosophy. It can be stated thus: a super-accurate, but [relatively] “slow” load “required him to have a Ph.D. in wind reading for every shot, while a faster, but less accurate load netted him more points.”
Note — this was not mere speculation; his score book data backed up his claims, due to less wind effects. Remember, however, this fellow has a consistent, National Championship-level hold, and other Champions on the same team would have opted differently.
Viewpoint THREE: Temperature Stability Is Key
Still another approach is to place heavy emphasis on fine accuracy with absolute stability in changing temperatures. When this writer was actively earning his Distinguished Rifleman badge, that was his goal. The reason? Sighting shots are not allowed in EIC (“Leg”) matches. The first shot out of the barrel was for score. It had to be 100% consistent, with very reliable, predictable elevation and wind deflection regardless of the ambient temperature — even if it wasn’t the lowest wind deflection possible.
Naturally, selecting a powder that is insensitive to temperature changes is a key element here. Elevation zeros and wind effects HAD to be consistent every time. Hunters and military snipers might be among those who fall into this camp, as well as those in pursuit of their Distinguished Rifleman badges.
Contrast that with a traditional High Power shooter who gets two sighter shots before each event (offhand, sitting rapid, prone rapid, prone slow fire.) If there is a zero change on any given day, he/she can correct during sighters. This writer well remembers talking with another very high-level Service Rifle competitor who was happy to have high temperatures boost the velocities of his ammunition above their usual level… As far as this SR competitor was concerned, 60-80 fps more velocity -– even if only due to high ambient temperatures -– meant less wind deflection, and he was mighty happy to have it.
Particularly in the summer, with hot daily conditions, you need to be concerned about temperature stability. Loads worked up in winter may not work in the summer time.
This article has been confined to NRA High Power Rifle competition, which has relatively generous 10-ring dimensions in relation to the accuracy of well-built competition rifles. Hopefully, it will provide food for thought. For some, this might be an opportunity to ensure that one’s load development approach helps them attain their desired results.
When shooting groups at long range on paper it can be difficult to distinguish which bullet holes belong to a particular sequence of shots. If, for example, you shot three 5-shot groups at 600+ yards on a paper target, you would have 15 bullet holes on the target (assuming no misses). But at that distance it would be difficult to see the holes on target (even with a spotting scope). Accordingly, when you inspected the target up close, it would be hard to tell which shots belonged to which group. You might have a vague idea, but couldn’t be sure, without a target camera recording the shot sequence.
Here is a method to separate multiple shots into specific groups so you can better evaluate your load and shooting skills. The trick is pretty simple — mark your bullets with a color from a Sharpie or other felt marking pen. If you are shooting three 5-shot groups, mark five with red, five with green, and five with blue (or purple). Then, when you inspect the target, you can identify the group placements by the colors that appear on the paper.
Round Robin: Using colors you can shoot “Round-Robin” to evaluate seating depths, neck tension, or other variables without having the shot order (and barrel heating) affect group sizes unequally. For example you might have three different neck tensions, each marked with a different color on the bullets. Then shoot Red, Blue, Green in that sequence for five total shots per color.
Smart Tip to Show Colors More Vividly
If the bullet inks are not showing up on your target paper clearly, here is a simple trick that can make the colors “bleed” to be more visible. In your range kit, bring some alcohol solution along with some Q-tips. Then dab the shots on the paper target lightly with wet Q-Tips. Here is the front of a target before and after application of alcohol:
Forum Member NewbieShooter explains: “Dabbing a bit of alcohol on the bullet holes with Q-Tips makes the color pop a bit… especially on the back side.” See below:
In short order you will see the colors spread into the paper, clearly marking the shot holes by distinguishing colors. If you were shooting a dark bullseye, view the the BACK side of the target to see the colors on a light background.
Credits: Bullet Tips photo by Forum Member Dave Way; Target photos by Forum Member NewbieShooter; Story tip from Boyd Allen.
Here are two different bullet types, seated to the same CBTO length, but different COAL. Note the shiny scratches on the bullets made by the comparator tool which indicates a point on the bullet ogive near where the ogive will engage the rifling.
Effects Of Cartridge Over All Length (COAL) And Cartridge Base To Ogive (CBTO) – Part 2 by Bryan Litz forBerger Bullets. Part One of this series focused on the importance of COAL in terms of SAAMI standards, magazine lengths, seating depths, and pressure levels. Another measure of length for loaded ammunition is highly important to precision, namely Cartridge Base to Bullet Ogive Length (CBTO).
Figure 2. Chamber throat geometry showing the bullet jump to the rifling or lands.
Look at Figure 2. Suppose the bullet was seated out of the case to the point where the base of the bullet’s nose (ogive) just contacted the beginning of the riflings (the lands) when the bolt was closed. This bullet seating configuration is referred to as touching the lands, or touching the riflings and is a very important measurement to understand for precision hand-loading. Due to the complex dynamics of internal ballistics which happen in the blink of an eye, the distance a bullet moves out of the case before it engages the riflings is highly critical to precision potential. Therefore, in order to systematically optimize the precision of his handloads, it’s critically important that the precision hand-loader understands how to alter bullet seating depth in relation to the barrel rifling. Part of the required knowledge is understanding how to accurately and repeatably measure the Cartridge Base To Ogive (CBTO) dimension. This is explained in the FULL ARTICLE.
Bryan Litz offers an extended discussion on how to measure CBTO using different tools and methods, including the Hornady OAL gauge. You can read this discussion in the full article found on the Berger Bullets website. CLICK HERE to Read Full Article.
Why Not Use CBTO as a SAAMI Standard?
If CBTO is so important to rifle accuracy, you might ask, “Why is it not listed as the SAAMI spec standard in addition to COAL?” There is one primary reason why it is not listed in the standard. This is the lack of uniformity in bullet nose shapes and measuring devices used to determine CBTO.
Benefits of Having a Uniform CBTO
There is another aspect to knowing your CBTO when checking your COAL as it pertains to performance. With good bullets, tooling, and carefully-prepared cases you can easily achieve a CBTO that varies less than +/- .001″ but your COAL can vary as much as .025″ extreme spread (or more with other brands). This is not necessarily bad and it is much better than the other way around. If you have a CBTO dimension that varies but your COAL dimension is tight (within +/- .002″) then it is most likely that your bullet is bottoming out inside the seater cone on the bullet tip. This is very bad and is to be avoided. It is normal for bullets to have precisely the same nose shape and it is also normal for these same bullets to have nose lengths that can vary as much as .025″.
Summary of Cartridge Base To Ogive (CBTO) Discussion
Here are four important considerations regarding bullet seating depth as it relates to CBTO:
1. CBTO is a critical measurement to understand for handloaders because it’s directly related to precision potential, and you control it by simply setting bullet seating depth.
2. Tools and methods for measuring CBTO vary. Most of the measurement techniques have pitfalls (which may give rise to inconsistent results) that you should understand before starting out.
3. A CBTO that produces the best precision in your rifle may not produce the best precision in someone else’s rifle. Even if you have the same rifle, same bullets, same model of comparator gauges, etc. It’s possible that the gauges are not actually the same, and measurements from one don’t translate to the same dimension for another.
4. Once you find the CBTO that produces the best precision in your rifle, it’s important to allow minimal variation in that dimension when producing quality handloads. This is achieved by using quality bullets, tooling, and properly preparing case mouths and necks for consistent seating.
This year Hornady Mfg. celebrates its 75th year in business. To mark this milestone, Midsouth is running a series of sales and special promotions. Plus Hornady offers free bullets with many reloading gear items including dies and presses. Founded in 1949 by Joyce Hornady, the company began making bullets in a rented garage in Grand Island, Nebraska. The business remains family-owned today.
Currently, nearly all Hornady products are discounted now at Midsouth. And — get this — product shipping is just $0.75 (seventy-five cents) for all Hornady product purchases of $75 or more. Enjoy the savings!
Below are noteworthy featured Hornady product deals:
Click to go to the Hornady Product Sales Page with Featured Deals
FREE Bullets with Purchase of Certain Hornady Products
Hornady is also offering 500 FREE bullets with the purchase of select Hornady Products such as press combo kits. And you get 100 free bullets with certain dies and reloading gear. Check it out:
Today, June 20, 2024 is Summer Solstice, the longest day of the year. And right now the Northeast USA is undergoing a major heatwave. That means “peak heat” summer conditions have arrived already. It’s vitally important to keep your ammo at “normal” temps during the hot summer months. Even if you use “temp-insensitive” powders, studies suggest that pressures can still rise dramatically when the entire cartridge gets hot, possibly because of primer heating.
It’s smart to keep your loaded ammo in an insulated storage unit, possibly with a Blue Ice Cool Pak if you expect it to get quite hot. Don’t leave your ammo in the car or truck — temps can exceed 140° in a vehicle parked in the sun.
The way ambient temperatures, barrel heating, and powder warming can affect cartridge pressures (and hence velocities) was covered in a study Pressure Factors: How Temperature, Powder, and Primer Affect Pressure by Denton Bramwell. In that article, the author used a pressure trace instrument to analyze how temperature affects ammo performance. Bramwell’s tests yielded some fascinating results.
For example, barrel temperature was a key factor: “Both barrel temperature and powder temperature are important variables, and they are not the same variable. If you fail to take barrel temperature into account while doing pressure testing, your test results will be very significantly affected. The effect of barrel temperature is around 204 PSI per F° for the Varget load. If you’re not controlling barrel temperature, you about as well might not bother controlling powder temperature, either. In the cases investigated, barrel temperature is a much stronger variable than powder temperature.”
This Editor had the personal experience of 6mmBR hand-loaded ammo that was allowed to sit in the hot sun for 45 minutes while steel targets were reset. The brass became quite warm to the touch, meaning the casings were well over 120° on the outside. When I then shot this ammo, the bullets impacted well high at 600 yards (compared to earlier in the day). Using a Magnetospeed, I then chron-tested the sun-heated ammo. The hot ammo’s velocity FPS had increased very significantly — all because I had left the ammo out in the hot sun uncovered for 3/4 of an hour.
LESSON: Keep your ammo cool! Keep loaded ammo in the shade, preferably under cover or in an insulated container. You can use a SEALED cool pack inside the container, but we do NOT recommend H20 ice packs. And don’t have the container do double duty for food and beverages.
Powder Heat Sensitivity Comparison Test
Our friend Cal Zant of the Precision Rifle Blog has published a fascinating comparison test of four powders: Hodgdon H4350, Hodgdon Varget, IMR 4451, and IMR 4166. The first two are Hodgdon Extreme powders, while the latter two are part of IMR’s Enduron line of propellants.
The testers measured the velocity of the powders over a wide temperature range, from 25° F to 140° F. Hodgdon H4350 proved to be the most temp stable of the four powders tested. [NOTE: New Alliant Reloder TS 15.5 has also proved very temp stable in AccurateShooter’s range tests.]
The Tactical Rifle Shooters Facebook Group recently showcased tools used to measure case headspace before and after “bumping” the shoulder. After a case is fired, hand-loaders who full-length size their cases will typically bump the shoulders back anywhere from .001″ to .0035″, depending on the rifle and application. With our 6mmBR and Dasher cases we like about .0015″ bump.
You want the amount of case sizing and bump to be the same for all your brass. To ensure uniformity, it makes sense to measure your cases before and after the FL sizing process. When we have time, we check every case. Other folks will simply check the first 3-4 cases coming out of the FL sizing die to ensure the FL die setting is correct and delivering desired headspace/bump.
1. Whidden Gunworks Shoulder Bump Gauge
There are a variety of tools that can be used to measure shoulder bump. Our favorite is a special cartridge-specific bushing made by Whidden Gunworks. The Whidden Shoulder Bump Gauge enables you to adjust your sizing die to the desired measurement. The bump gauge is attached to your calipers with a set screw and determines the measurement from the base to the shoulder of the case. The photo below, from Tactical Rifle Shooters, shows the Whidden Bump Gauge for the .375 CheyTac cartridge.
2. Dave Manson Vertical Comparator with Dial Read-Out
Dave Manson states: “This tool was designed to make life easier for the advanced shooter and re-loader by allowing precise measurement of ammunition, case, and chamber headspace. With this information, the re-loader will be able to fine-tune clearances and fits between his ammunition and chamber, with resultant improvements in accuracy and case life.” The functions of the Manson Comparator are:
1. Measure headspace of factory or reloaded ammunition
2. Quantify chamber headspace by measuring headspace of a fired case
3. Ensure minimal shoulder set-back when setting up re-loading dies
4. Compare base-to-ogive length to ensure consistent bullet-to-rifling relationship.
Hornady’s Lock-N-Load Headspace Comparator system is easy-to-use and handy. You can get a kit with Red bushing-holder body and 5 bushings for $39.99 at Midsouth. Hornady explains: “The Lock-N-Load® Headspace Comparator… gauge measures variations in brass before and after firing or re-sizing. It allows for headspace comparison between fire-formed brass and re-sized brass.” IMPORTANT: Hornady states: “To determine the proper bushing diameter for your cartridge, simply add the neck diameter and the shoulder diameter and divide that number by two. Use the bushing closest to that number.” Hornady offers five: .330″, .350″, .375″, .400″, and .420″.
One tip — We have found the Hornady gauges may vary a little from unit to unit even with the same nominal size. If you have more than one gauge for the same cartridge, test each on your brass — you may then note a slight difference in your bump measurements. Mark one and use that consistently. There is also an Anvil Base Kit that mounts to the opposite blade on the caliper. This provides a more stable surface for the base of your case.
4. L.E. Wilson Case Gage Depth Micrometer
If you are looking for precise “bump” measurements without having to mess with calipers and clamp-on gauge blocks, you may want to consider the L.E. Wilson Case Gage Depth Micrometer (currently $130.00). This takes very precise, repeatable measurements, but you need to know your starting point. The manufacturer explains: “Every reloader should know exactly how much your Full Length Sizing Die is pushing back the shoulder. With the NEW Case Gage Depth Micrometer you can do just that! It has never been easier to measure you cases headspace before and after sizing. The Depth Mic allows you to slip the micrometer perfectly over the top of the Gage with your case inserted into the Gage and take a measurement. Micrometer has graduations of .001″. The Case Gage Depth Micrometer is set to a zero of .100″ on the scale at our factory. Because of differences in ‘feel’ and temperature, we include a the Gage Block for you to test Zero and to adjust if necessary.”
5. Pistol Brass Case DIY Bump Gauge
Last is a “field expedient” set-up if you do not have any of the comparator tools shown above. A sized .45 ACP case (or other suitable pistol case) can be used to measure shoulder bump. The mouth of the pistol case sits on the shoulder of your rifle cartridge brass.
Make sure the .45 ACP case is trimmed square and that it is round. We recommend you first run it through an expander, then size it, trim it and chamfer. Next, take the .45 ACP case and slip it over the neck of a fired, unsized rifle case with the primer removed. Align the two cases between the jaws of your calipers and note the length from rim to rim (See left photo below).
OK, now you have the length for a fired rifle case BEFORE sizing. Next, take a full-length sized rifle case (without primer) and do the same thing, placing the .45 ACP case over the neck of the FL-sized case (Right Photo). The difference between the two numbers is the amount of “bump” or set-back you are applying to the shoulder. Here the difference is .0015″. The amount of bump you need varies with your chamber and your load, but .0015-.002″ is a good initial setting.
At the request of our readers, we provide select “Deals of the Week”. Every Sunday afternoon or Monday morning we offer our Best Bargain selections. Here are some of the best deals on firearms, hardware, reloading components, optics, and shooting accessories. Be aware that sale prices are subject to change, and once clearance inventory is sold, it’s gone for good. You snooze you lose.
NOTE: All listed products are for sale to persons 18 years of age or older. No products are intended for use by minors.
1. Brownells — Weekly Featured Deals
⏺ Great savings on large variety of products at Brownells
⏺ Huge discounts on quality Sightron scopes — save up to $820.00
Creedmoor Sports is running a major sale on Sightron Scopes currently. Save up to $820 off MSRP. Sightron scopes are popular with varminters and competitors because they are very reliable, with clarity, sharpness, and precision that rival optics costing hundreds more. Long-range benchrest and F-Class competitors should consider the impressive Sightron SIII LR 10-50x60mm scope, now just $1479.99, a $370 savings off the regular price.
3. Precision Reloading — Major Hornady 10% Off Sale
⏺ Save 10% on ammo, brass, bullets, dies, reloading tools
Though June 7, 2024, Precision Reloading is running a big Hornady 10% Off Sale. Pretty much all Hornady brand products will be discounted 10%. CLICK HERE to see all the Hornady items currently on sale. Among the many Hornady products we like are: pistol dies, varmint bullets, hunting ammo, One-Shot Case Lube, Bullet Comparator Set, and L-N-L Iron Press.
4. Natchez — CCI, Federal, Remington Primer Sale
⏺ Good prices on primers at Natchez this week
Quality American-made primers continue to be in high demand with prices still much higher than before the pandemic. However, Natchez is now running a major primers sale. You’ll find a wide selection of rifle, pistol, and shotshell primers at good prices. Primers on sale include CCI, Federal, and Remington. Save up to $45 per 1000ct primer package.
5. Amazon — Real Avid Workstation, $159.99
⏺ Versatile gun vise/workstation, with good user reviews
Cleaning or working on rifles requires a good rest, ideally one that has strong mounts plus ample adjustment range. The Real Avid Workbench has those qualities. It will hold your rifle securely AND can do multiple tasks via Real Avid’s optional Smart-Assist accessories. These include a work light, magnifying glass, and cell phone holder, all mounted on flexible goosenecks. The basic Real Avid Gun vise/Workbench is $159.99 on Amazon (#ad), 20% off this week.
6. Al’s — Frankford Arsenal Case Trim & Prep Center, $164.99
⏺ Excellent multi-drive case prep machine with very complete tool set
Good case prep is critical to making precision loads. One of the best case prep machines on the market is the Frankford Arsenal Case Trim and Prep Center. This machine boasts a strong center motor and three accessory tool drives. This FA Case Prep unit ships with a full set of tools: inside chamfer tool, deburr tool, primer pocket cleaning tools, and a trimmer with 3 collets + 6 shoulder bushings.
7. Brownells — Sinclair and RCBS Hand Priming Tools
⏺ Two very good choices for hand priming — single and tray-feed
The Sinclair Priming Tool offers very precise primer seating with an ultra-consistent “feel”. The tool head utilizes Sinclair shellholders and locks the case head square to the priming punch. This tool has excellent leverage, yet it is extremely sensitive so you can feel the primer entering the primer pocket and bottoming out. If you want to prime larger quantities of brass more quickly, consider the RCBS Universal Hand Priming Tool. This can hold 100 primers in the attached tray. The spring-loaded gripper lets you switch quickly between small and large case rim sizes. SEE RCBS Priming Tool Video.
8. Amazon — LEE Hand Press Kit, $76.94
⏺ Versatile hand press can be used at range or at home
No matter how much reloading equipment a reloader has, it makes sense to have a portable hand press. This can help you load at the range when doing load development. And back home you can use the hand press for tasks such as decapping primers and bullet seating. Now priced at just $76.94 on Amazon the LEE Hand Press Kit (#ad) includes powder funnel, priming insert, case lube and other accessories. This versatile Hand Press Kit is well worth the money.
9. Amazon — MEIJIA 53.5″ Hard Rifle Case, $119.99
⏺ Good case for long-barreled rifle, half the cost of similar cases
In a vehicle or on a plane, hard cases are the safest way to transport your firearms, but the most rugged and protective cases usually come with a hefty price tag. Here’s an affordable hard case that still offers great protection for big, long-barreled match rifles. The 53.5″-long MEIJIA All Weather Hard Rifle Case (#ad) measures 52.2″ inside — big enough to handle 31″+ barrels. This rugged, waterproof case has nice, thick foam (pluckable to customize), and has good locking points.
As an Amazon affiliate, this site can earn revenues through sales commissions.
by Sierra Bullets Ballistic Technician Paul Box
All of us who have been in reloading and shooting for any period of time have read how sectional density has been regarded as a bullet’s ability to penetrate. Back before high velocity came along and modern bullet design, the easiest way to get more “power” and penetration was by increasing the diameter and mass. After all, a bowling ball will hurt more than a golf ball, right?
Let’s take a closer look at sectional density.
The formula for calculating sectional density is pretty simple and straight forward. Take the bullet weight and divide by 7000. This number is then divided by the bullet diameter squared. Two bullets of equal weight and the same diameter will have equal sectional sectional density. No regard is given to the bullet construction. This is where the fly hits the soup in considering sectional density as far as penetration is concerned.
Section Density Formula: (Bullet Weight divided by 7000) divided by Bullet Diameter squared.
Bullet construction is the biggest factor in how it is able to penetrate. The best example I can think of here is to look at the Sierra .224 55 Gr. FMJBT GameKing #1355 compared to the 55 Gr. BlitzKing #1455. Both are .224 and weigh 55 grs. Both have a sectional density of .157. But there is a huge difference in their construction. The FMJ has a thick jacket and is designed to penetrate. The BlitzKing is designed for fast and rapid expansion with little concern for how deep they will penetrate.
The next time you’re choosing a bullet, look at the construction and less at the sectional density number. It’s all about the construction anyway. If you have any questions or would like to discuss sectional density or bullet penetration further, please give us a call at 800-223-8799 or shoot us an email at sierra@sierrabullets.com.
Sierra Bullets has published load data for the 6mm Creedmoor cartridge, a necked-down version of the popular 6.5 Creedmoor. Sierra has released very comprehensive 6mm Creedmoor load data, covering fifteen (15) different bullets from 55 to 110 grains. NOTE: Hornady-brand brass was used for Sierra’s 6mm Creedmoor load tests, not the newer, stronger Lapua 6.5 CM brass with small primer pockets. Hand-loaders using Lapua 6.5 Creedmoor brass necked to 6mm may have to adjust their loads.
Sierra writes: “As soon as the 6.5 Creedmoor was released in 2007, a 6mm version was being envisioned. After the 6mm Creedmoor demonstrated its worth at 1000 yards it began to catch the attention of Precision Rifle Series (PRS) competitors. The 6mm Creedmoor is a great fit for those looking for an AR platform-friendly cartridge. It delivers velocities very similar to the .243 Win and yet fits the AR10 magazine length[.] The 30-degree shoulder makes this a very efficient case and helps prolong case life as well. The 6mm Creedmoor works well with powders such as H4350, [RE-16], RE-17, and Ramshot Hunter for heavier long-range bullet weights. Slightly faster powders such as RE-15, Win 760, and Vihtavuori N540 work well with lighter weight bullets.”
Sierra Bullets Tested for 6mm Creedmoor Load Data
55gr BlitzKing (#1502)
60gr HP (#1500)
70gr HPBT (#1505)
70gr BlitzKing (#1507)
75gr HP (#1510)
In developing its 6mm Creedmoor load data, Sierra tested a very wide selection of propellants, two dozen overall. For the smaller bullets, fast-burning powders such as Benchmark, H4895, and CFE223 were tested. For the heavier 100+ grain bullets, Sierra tested a selection of medium-burn-rate powders including H4350, Reloder 16, Reloder 17, Varget, and Superformance. Sierra did a very thorough job. We know this information will be welcomed by 6mm Creedmoor shooters.
Don’t know what powder to try first? For the 107-110 grain bullets, if you want best accuracy and low ES/SD, our Forum members recommend Alliant Reloder 16 and Hodgdon H4350. If you are seeking max velocity with the 110-grainer, look at Hodgdon Superformance and Reloder 19.
Here are Sierra’s 6mm Creedmoor Load Data Charts for 90-95 grain bullets plus the 107gr MK and 110gr MK. There are five other tables for other bullet types.
BONUS: PRB 6mm Creedmoor and 6.5 Creedmoor Load Survey
The Precision Rifle Blog compiled Load Data from PRS Competitors, for both 6mm Creedmoor and 6.5 Creedmoor. This is a good place to start. PRB surveyed the match loads for “173 of the top-ranked precision rifle shooters in the country”. One cautionary note: These PRS guys may be loading fairly hot, so work up gradually, 0.3 grains at a time. CLICK HERE.
At the request of our readers, we provide select “Deals of the Week”. Every Sunday afternoon or Monday morning we offer our Best Bargain selections. Here are some of the best deals on firearms, hardware, reloading components, optics, and shooting accessories. Be aware that sale prices are subject to change, and once clearance inventory is sold, it’s gone for good. You snooze you lose.
NOTE: All listed products are for sale to persons 18 years of age or older. No products are intended for use by minors.
1. Brownells — Weekly Featured Deals and Memorial Day Sale
⏺ Great deals at Brownells — ammo, bullets, optics, chronos, and more
2. EuroOptic — 50% Off Vortex for Military, LE, First Responders
⏺ 50% Off MSRP for Military, police, first responders through 5/30/24
Today (5/27/24) is Memorial Day. To help mark this day, Vortex, via EuroOptic, has a special promotion with 50% off MSRP for Vortex products. This offer runs through May 30, 2024. After that a similar Military/LE/First Responder discount may be available at 40% off MSRP. CLICK HERE for more information. To qualify you must set up a user account. The offer excludes close-outs and discontinued items.
3. Primary Arms — Memorial Day Sale, Save up to 30%
⏺ Major savings on hundreds of items — great for AR components
Primary Arms is running a big Memorial Day Sale with hundreds of items on Sale. Along with the featured special, you can shop for deals by Manufacturer/Brand (e.g. Vortex, EoTech, Magpul) or by Product Category (e.g. Optics, Barrels, Ammo, AR Uppers). Shown above are four noteworthy deals, but there are over 2000 items discounted.
4. Midsouth — Peterson Brass on Sale, 24 Varieties
⏺ High quality, long lasting brass — good PRS/NRL choice
Excellent American-made Peterson brass is on sale now at Midsouth. You’ll find many 6mm options including 6mm Dasher and 6mm Creedmoor. If you shoot a Dasher, this Peterson brass will let you avoid the time and expense of fire-forming cases. Hunters will be pleased to find a number of large magnum cartridge types available including 7mm PRC, 7mm RUM, .300 WinMag, .300 Norma Mag, 33 Nosler, .338 Lapua Magnum, and more.
5. MidwayUSA — ATN Day/Night 3-14X Video Scope, $559.00
⏺ Advanced scope records video and operates daytime and night-time
Here’s a great electro-optics product for hunters. The 3-14X ATN X-Sight scope offers day/night viewing capability, PLUS it can record HD video of your hunt. This scope even has a built-in Ballistics Calculator that shows hold-overs. Right now this 3-14X optic is $559.00 at MidwayUSA, a $140.00 (20%) discount. In addition to the ATN 3-14X model, there is a 5-20X version for $639.00 on sale at Midway USA. Both models offer HD video recording, ballistics, electronic compass, multiple reticle options, and smartphone connectivity. BONUS: Both 3-14X and 5-20X ATN optics ship with 30mm Picatinny rings.
6. Creedmoor Sports — Berger 6mm, 6.5mm, 7mm Bullets Sale
⏺ Good prices on top-tier Berger match bullets
Berger bullets are favored by top competitors in many disciplines. Right now you can get significant savings on popular Berger match bullets in 6mm, 6.5mm, and 7mm calibers. F-Class shooters — take note that Berger 180gr Match Hybrid Target bullets and 184gr F-Open Hybrid Target bullets are on sale — save $10 per hundred. Along with the savings on top-tier bullets, through 5/28/24 you can get FREE Shipping with orders over $149.00. Use Creedmoor Sports discount code REMEMBER.
7. Amazon — Lyman BrassSmith Funnel, $31.99
⏺ Very useful kit we use — avoids powder spills
Having a good powder funnel really helps precision reloading. The Lyman Products Brass Smith Pro Powder Funnel System (#ad) is a great little system. Unlike plastic powder funnels, the aluminum DIE cast body and CNC-turned aluminum caliber-specific inserts are static free to eliminate powder cling. The precision fit to your case necks eliminates spilled powder. The kit includes six laser-marked aluminum inserts to fit calibers 22 to 338: .22, .243/6mm, .25/6.5mm, .270/7mm, .30, and .338.
8. Midsouth — CCI Blazer .22 LR Ammo, $32.99/500 Rounds
⏺ Very low price on good, reliable .22 LR ammunition
If you use .22 LR ammo for NRL22, varminting, or plinking, consider this CCI Blazer 40gr ammunition. Rated at 1235 fps, this CCI ammo runs pretty fast and packs a punch. Right now you can get a 500-ct brick for just $32.99. That’s just $3.29 per 50-ct box, a great value for quality American-made ammo.
9. MidwayUSA — Plano Protector Pro-Max Rifle Case, $33.99
⏺ Good price on a sturdy, 52″ interior transport case for long rifles
Do you have a long-barreled hunting or varmint rifle? With a 52″ internal size, this Plano Protector Pro-Max Rifle Case handles rifles with barrels up to 30″ (or 31″ with a thin buttplate). On the inside the case has high-density, interlocking foam padding. On the outside, the case has four clamps, padlock tabs, and a handy carry handle. NOTE: This case will work well for normal trips to the range. However, you’ll want a thicker, more sturdy TSA-approved case for airline transport.
⏺ Under $20 for versatile, multi-lens Eye Protection
All shooters need quality eye protection when operating firearms. XAegis Tac Eyewear is a versatile and affordable option. These ANSI Z87+ rated shooting glasses come with three different interchangeable lenses (Clear, Yellow, Gray). You also get a transport case, lanyard, and cleaning cloth. Choose from three frame colors, each for $18.99: Black frame, Green Frame, or Khaki frame. For under $20 these are hard to beat. It’s nice to have the color lens options for different weather conditions, and indoors/outdoors.
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Effects Of Cartridge Over All Length (COAL) And Cartridge Base To Ogive (CBTO) – Part 2
The way ambient temperatures, barrel heating, and powder warming can affect cartridge pressures (and hence velocities) was covered in a study Pressure Factors: How Temperature, Powder, and Primer Affect Pressure by Denton Bramwell. In that article, the author used a pressure trace instrument to analyze how temperature affects ammo performance. Bramwell’s tests yielded some fascinating results.
