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September 18th, 2016
Why You CANNOT Rely on the MV Printed on the Ammo Box!
When figuring out your come-ups with a ballistics solver or drop chart it’s “mission critical” to have an accurate muzzle velocity (MV). When shooting factory ammo, it’s tempting to use the manufacturer-provided MV which may be printed on the package. That’s not such a great idea says Bryan Litz of Applied Ballistics. Don’t rely on the MV on the box, Bryan advises — you should take out your chrono and run your own velocity tests. There are a number of reasons why the MV values on ammo packaging may be inaccurate. Below is a discussion of factory ammo MV from the Applied Ballistics Facebook Page.
Five Reasons You Cannot Trust the Velocity on a Box of Ammo:
1. You have no idea about the rifle used for the MV test.
2. You have no idea what atmospheric conditions were during testing, and yes it matters a lot.
3. You have no idea of the SD for the factory ammo, and how the manufacturer derived the MV from that SD. (Marketing plays a role here).
4. You have no idea of the precision and quality of chronograph(s) used for velocity testing.
5. You have no idea if the manufacturer used the raw velocity, or back-calculated the MV. The BC used to back track that data is also unknown.
1. The factory test rifle and your rifle are not the same. Aside from having a different chamber, and possibly barrel length some other things are important too like the barrel twist rate, and how much wear was in the barrel. Was it just recently cleaned, has it ever been cleaned? You simply don’t know anything about the rifle used in testing.
2. Temperature and Humidity conditions may be quite different (than during testing). Temperature has a physical effect on powder, which changes how it burns. Couple this with the fact that different powders can vary in temp-stability quite a bit. You just don’t know what the conditions at the time of testing were. Also a lot of factory ammunition is loaded with powder that is meter friendly. Meter friendly can often times be ball powder, which is less temperature stable than stick powder often times.
3. The ammo’s Standard Deviation (SD) is unknown. You will often notice that while MV is often listed on ammo packages, Standard Deviation (normally) is not. It is not uncommon for factory ammunition to have an SD of 18 or higher. Sometimes as high as 40+. As such is the nature of metering powder. With marketing in mind, did they pick the high, low, or average end of the SD? We really don’t know. You won’t either until you test it for yourself. For hand-loaded ammo, to be considered around 10 fps or less. Having a high SD is often the nature of metered powder and factory loads. The image below is from Modern Advancements in Long Range Shooting: Volume II.
4. You don’t know how MV was measured. What chronograph system did the manufacturer use, and how did they back track to a muzzle velocity? A chronograph does not measure true velocity at the muzzle; it simply measures velocity at the location it is sitting. So you need to back-calculate the distance from the chrono to the end of the barrel. This calculation requires a semi-accurate BC. So whose BC was used to back track to the muzzle or did the manufacturer even do that? Did they simply print the numbers displayed by the chronograph? What kind of chronograph setup did they use? We know from our Lab Testing that not all chronographs are created equal. Without knowing what chronograph was used, you have no idea the quality of the measurement. See: Applied Ballistics Chronograph Chapter Excerpt.
5. The MV data may not be current. Does the manufacturer update that data for every lot? Or is it the same data from years ago? Some manufacturers rarely if ever re-test and update information. Some update it every lot (ABM Ammo is actually tested every single lot for 1% consistency). Without knowing this information, you could be using data for years ago.
CONCLUSION: Never use the printed MV off a box of ammo as anything more than a starting point, there are too many factors to account for. You must always either test for the MV with a chronograph, or use carefully obtained, live fire data. When you are using a Ballistic Solver such as the AB Apps or Devices integrated with AB, you need to know the MV to an accuracy down to 5 fps. The more reliable the MV number, the better your ballistics solutions.
September 16th, 2016
Click image for Online Reloading Data. CLICK HERE for Printable PDF Reloading Guide.
Vihtavuori has updated and enhanced its reloading information, adding VV powder load recipes for many more cartridge types. Data is now online for 64 rifle cartridge types and 26 pistol cartridge types. You’ll find the updated reloading data on the Vihtavuori Website. Bookmark this link: www.vihtavuori.com/en/reloading-data/about-reloading.html.
The updated online information supplements the Vihtavuori Reloading Guide (2016 Edition) available in PDF format. The online Reloading Database has dedicated sections for Rifle Cartridges, Pistol Cartridges, and Cowboy Action. There is also a handy, FREE Reload Mobile App for iOS and Android.
Rifle Reloading Data
Vihtavuori’s Rifle Reloading Database is now very comprehensive. Many of the popular modern match cartridges such as the 6.5×47 Lapua and 6.5 Creedmoor are now included, and of course you’ll find the 6mm PPC, 6mmBR, and 6XC. (There is no .284 Win or 7mm RSAUM data unfortunately.) You will find recommended load recipes for all the following cartridges:
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.204 Ruger
.221 Remington Fireball
.222 Remington
.22 Hornet
.22 PPC-USA
.223 Remington
.22-250 Remington
.223 WSSM
.243 Winchester
.243 WSSM
6mm PPC-USA
6mmBR Norma
6 XC
6mm Remington
.240 Weatherby Magnum
6.5 Grendel
6.5 x 47 Lapua
6.5 Creedmoor
6,5 x 55 Swedish Mauser
6,5 x 55 Swedish Mauser/ SKAN
6.5-284 Norma
.25-06 Remington
.260 Remington
.270 Winchester
.270 WSM
.270 Weatherby Magnum
7 mm-08 Remington
7 x 57
7 x 64
7 mm Remington Magnum
7 mm WSM
7 mm RUM |
7 x 57R
7 mm Weatherby Magnum
7,5 x 55 Swiss GP31
.30 Carbine
.30-30 Winchester
.300 AAC Blackout
7,62 x 39
.300 Savage
7,62 x 53R (7,62 Russian)
.308 Winchester
.30-06 Springfield
.300 Lapua Magnum
.300 Remington Ultra Magnum
.300 Winchester Magnum
.300 Weatherby Magnum
.30-.378 Weatherby Magnum
.300 H&H Magnum
.300 WSM
.303 British
8 x 57 IRS
8 x 57 IS (8 mm Mauser)
.338 Winchester Magnum
.338 Lapua Magnum
9,3 x 62
9,3 x 66 Sako
9,3 x 74R
.375 H&H Magnum
.416 Rigby
.444 Marlin
.45-70 Government
.458 Winchester Magnum
.50 Browning |
Handgun Reloading Data
Likewise, VV’s Handgun Reloading Database is extensive. These pistol cartridges are covered:
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.32 S&W Long N.P.
.32 S&W Long Wadcutter
.357 Remington Maximum
.357 Magnum
.357 SIG
.38 Super Lapua
.38 Super Auto
.38 Special
7 mm GJW
7 mm TCU
7 mm BR Remington
7,62 x 25 Tokarev
9 mm Luger |
9 x 21
9 x 23 Winchester
.40 S&W
10 mm AUTO
.41 Remington Magnum
.44 S&W Special
.44 Remington Magnum
.45 ACP
.45 Colt
.45 Winchester Magnum
.454 Casull
.500 S&W Magnum
.50 AE |
Story Tip by EdLongrange. We welcome reader submissions.
September 12th, 2016
At the request of our readers, we provide select “Deals of the Week”. Every Monday morning we offer our Bargain selections. Here are some of the best deals on firearms, hardware, reloading components, 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.
1. Stocky’s Stocks — Composite Stock with Bedding Block, $199.99
Here’s a killer deal on a versatile Stocky’s Long Range Stock with aluminum V-block bedding system. For just $199.99, order this for Rem/Rem Clone long actions or short actions, with either narrow or wide (varmint/tactical) barrel channel. This would be a good choice for a varmint rifle. This is also offered with a matte black, tan, or olive baked-on textured finish for $239.99.
2. Sportsmans — .45 ACP Ammo, 300 Rds $84.95 with Rebate
 The .45 ACP is probably our favorite centerfire pistol cartridge. It is reliable, inherently accurate, and makes big, easy-to-see holes in paper. Here’s a good deal for .45 ACP shooters. Sportsmans Outdoor Superstore is selling 300 rounds of American Eagle .45 ACP 230gr FMJ ammo for $114.95 in a handy plastic ammo can. And with factory rebate, you can knock thirty bucks off that price. Through the end of 2016, Federal Ammunition is offering $30.00 cash back on this ammo. CLICK HERE for Rebate Form.
Fine Print: Maximum of $30.00 rebate. Purchase must be made before December 31, 2016. Coupon must be received by January 31, 2017. Consumer submits coupon with UPCs written and original cash register receipt and/or dated itemized sales invoice (photocopies not accepted). Please allow 6-8 weeks for delivery. Total redemptions limited to five (5) of each product per name, address and household.
3. Natchez — Special 5 Reloading Press Kit, $199.99
This is an excellent entry-level reloading kit, which is on sale for $199.99 at Natchez Shooters Supplies. We like the relatively compact Special 5 press for most reloading duties. Eventually you may want to add an additional, large heavy press, but this will get the job done. This kit includes an RCBS Powder Measure, Digital Scale, Powder Trickler, Hand Priming Tool, Load Manual, Loading Tray, and more. It’s hard to beat this combination of tools for under $200.00.
4. Southern Shooters — 17 HMR Ruger American Rimfire. $252.63
With ballistics far superior to a .22 LR, the 17 HMR is ideal for Prairie Dogs and small varmints out to 180 yards or so. Now you can get a reliable, name brand 17 HMR rifle for a very attractive price. That’s right, Southern Shooters is selling the 17 HMR Ruger American Rimfire, with 22″ barrel, for just $252.63. FFL required. For other vendors with this rifle, CLICK HERE.
5. Amazon — Lyman Case Prep Xpress $94.99
The Lyman Case Prep Xpress lets you chamfer inside and out, brush your necks, clean/uniform primer pockets, and ream military crimps. On sale at Amazon.com with $94.99 Prime pricing, this is a good deal. Lyman’s Case Prep Xpress sells elsewhere for $130.00 or more. Here is a review from a Verified Purchaser: “The unit is quiet, sturdy, and the attachments do what they are supposed to do. It already has made a difference in my reloading speed, and most importantly, my comfort. I highly recommend this unit.” (Strafer, 4/7/14)
6. Natchez Shooters Supply — 325 Rounds .22 LR Ammo, $22.99
This Federal .22 LR ammo is just 7 cents per round — the kind of pricing on bulk rimfire ammo we used to see in the “good old days”. Act quickly, this $22.99 Federal .22 LR Ammo deal won’t last long. Each box contains 325 rounds — enough ammo for many sessions at the range. The bullets are 40 grains, solid lead.
7. Sportsman’s Guide — Frankford Arsenal Case Tumbler Kit
For just $69.99, this Frankford Arsenal Kit provides everything you need to clean brass: Vibratory Tumbler, Rotary Media Separator, Bucket, Corn Cob Media (3 lbs.), and Brass Polish. The Case Tumbler holds up to 600 9mm cases or 350 .223 Rem cases. The separator system is generous, with a 3.5-gallon bucket. NOTE: Sportsman’s Guide Buyers Club members can purchase for $62.99.
8. Amazon — Neiko Digital Calipers, $17.74
Even if you have a good set of calipers, you may want to get one of these Neiko 01407A Digital Calipers. The #1 best-selling digital caliper on Amazon.com, this Neiko tool features a large LCD Screen and measures up to 6.0 inches. With over 2300 customer reviews, this product has earned an overall rating of 4.4 out of 5 stars. It’s hard to go wrong for $17.74, even if you just use these as a spare set for measuring group sizes and case trim lengths.
September 8th, 2016
Coating bullets with a friction-reducing compound such as Molybdenum Disulfide (Moly) offers potential benefits, including reduced barrel heat, and being able to shoot longer strings of fire between bore cleanings. One of the effects of reduced friction can be the lessening of internal barrel pressures. This, in turn, means that coated bullets may run slower than naked bullets (with charges held equal). To restore velocities, shooters running coated bullets are inclined to “bump up” the load — but you need to be cautious.
Be Careful When Increasing Loads for Coated Bullets
We caution shooters that when your start out with coated bullets in a “fresh barrel” you should NOT immediately raise the charge weight. It may take a couple dozen coated rounds before the anti-friction coating is distributed through the bore, and you really start to see the reduced pressures. Some guys will automatically add a grain or so to recommended “naked” bullet charge weights when they shoot coated bullets. That’s a risky undertaking.
Instead we recommend that you use “naked” bullet loads for the first dozen coated rounds through a new barrel. Use a chronograph and monitor velocities. It may take up to 30 rounds before you see a reduction in velocity of 30-50 fps that indicates that your anti-friction coating is fully effective.
We have a friend who was recently testing moly-coated 6mm bullets in a 6-6.5×47. Moly had not been used in the barrel before. Our friend had added a grain to his “naked” bullet load, thinking that would compensate for the predicted lower pressures. What he found instead was that his loads were WAY too hot initially. It took 30+ moly-coated rounds through the bore before he saw his velocities drop — a sign that the pressure had lowered due to the moly. For the rounds fired before that point his pressures were too high, and he ended up tossing some expensive Lapua brass into the trash because the primer pockets had expanded excessively.
LESSON: Start low, even with coated bullets. Don’t increase your charge weights (over naked bullet loads) until you have clear evidence of lower pressure and reduced velocity.
Procedure After Barrel Cleaning
If you shoot Moly, and clean the barrel aggressively after a match, you may want to shoot a dozen coated “foulers” before starting your record string. Robert Whitley, who has used Moly in some of his rifles, tells us he liked to have 10-15 coated rounds through the bore before commencing record fire. In a “squeaky-clean” bore, you won’t get the full “benefits” of moly immediately.
 To learn more about the properties of dry lubricants for bullets, read our Guide to Coating Bullets. This covers the three most popular bullet coatings: Molybdenum Disulfide (Moly), Tungsten Disulfide (WS2 or ‘Danzac’), and Hexagonal Boron Nitride (HBN). The article discusses the pros and cons of the different bullet coatings and offers step-by-step, illustrated instructions on how to coat your bullets using a tumbler.
September 4th, 2016
At the request of our readers, we provide select “Deals of the Week”. Each week we offer our Bargain selections. Here are some of the best deals on firearms, hardware, reloading components, 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.
LABOR DAY HOLIDAY SPECIALS
We are publishing our Deals on Sunday this week because many of the best bargains are Labor Day Weekend Specials. There are also Special 10% OFF PROMOTIONS running this weekend. We want readers to be able to take advantage of these holiday specials before the discount codes “time out”.
1. Brownells — Labor Day Weekend Sale & Free Shipping ($99+)
Brownells is offering great pricing on a host of products this weekend. You’ll find bargains on Berger Bullets, RCBS Rockchuckers, AR components, Timney Triggers, Magpul Stocks, Rimfire Ammo, Centerfire Ammo, Range Bags, and more. Plus all Geissele products are on sale this holiday weekend. In addition, with CODE L27 you can FREE Ground Shipping on orders over $99.00. This free shipping offer expires on 9/5/2016 at 11:59 PM CST. CLICK HERE for Labor Day Specials.
2. Amazon — Vortex 4-12x50mm AO Scope, $174.00
The NRA is introducing a new Mid-Range Tactical Prone Match for AR platform rifles with bipods. Optics up to 12X will be allowed. If you’re considering participating in this new Mid-Range competition, here’s a fine Vortex 4-12x50mm AO Crossfire II scope for under $175.00. That’s a steal. This second-focal-plane scope features front parallax adjustment and a BDC reticle. Put the money you save on optics into a premium barrel and quality match trigger.
3. Ammomen — Winchester .22 LR Ammo $15.50 for 235 Rounds
We are finally starting to see .22 LR rimfire ammo come down to very affordable levels. With this Winchester bulk pack special you get 235 rounds for just $15.50. That works out to just 6.6 cents per round (or $3.30 for 50 rounds). This .22 LR ammo is loaded with 36 grain copper-plated lead HP bullets. The ammo is rated at 1280 fps in rifles, 1085 fps in pistol.
4. Savage Arms — Rifle Rebates up to $75.00
With the Save on a Savage Rebate, you can get $75.00 on Savage Trophy Hunter, DOA Hunter, Model 14/114 or Model 16/116; or get $30.00 back on any AXIS or A17™ synthetic stock rifle. Shooters who purchase any bolt-action Savage rimfire, including the B.MAG and Rascal, will be eligible for a $25 mail-in rebate. Firearms must be purchased between August 11, 2016 and September 25, 2016. NOTE: This program also includes the popular semi-auto A17 17 HMR which was voted ‘Rifle of the Year’ by both NRA American Hunter and Guns & Ammo magazines. CLICK HERE for Rebate Coupon.
5. Cabelas — 10% Off Labor Day Special with Free Shipping
Act quickly guys, this Cabelas.com offer expires 9/5/16, at 11:59 pm Eastern Time. Throughout the Labor Day Weekend you can get 10% off most online merchandise, plus FREE Shipping for orders over $99.00. This includes ammo purchases, but not firearms. This is an online-only promotion, not valid at Cabela’s retail stores. Use Code 6TENOFF during online checkout. Some heavy or oversized items will require paid shipping and handling.
6. Amazon — Leight MAX NRR33 Earplugs, $7.50 for 50 Pairs
These Howard Leight NRR33 Max plugs are your Editor’s favorite foam earplugs. Between shooting, motorcycling and mowing lawns, I probably have Max plugs in my ears 2-3 days a week. This is a very good price for a bulk pack of 50 pairs. And if you act soon, you can get free shipping to boot.
7. Beretta USA — Labor Day Sale, Up to 60% Off
Beretta is offering big discounts — up to 60% Off — during its Labor Day Outlet Store Sale. You can save on shooting accessories, clothing, gun cases, holsters, gunstocks, choke tubes, barrels, scope rings, grips and much more. You’ll also find great deals on Tikka and Sako stocks (Beretta is the distributor for Tikka and Sako). For example, a high-grade Sako 75 Hunter DLX stock is marked down from $878.00 to $439.00. In addition, Beretta is offering Free Shipping on Orders over $89.00.
8. Precision Reloading — $15 Hazmat Fees on Powder and Primers
If you’re purchasing powder, primers and other Hazmat items, you can save up to $25.00 per order with this offer from our friends at Precision Reloading. Some vendors charge as much as $40.00 for Hazmat fees (on top of regular shipping). This fall Precision Reloading is lowering its Hazmat charge to just $15.00 per order. And yes, you can combine powder and primers in the same order. NOTE: Normal shipping charges apply, and total package weight may not exceed 70 pounds.
September 2nd, 2016
Smokeless Powder Photo courtesy GunsAmerica.com, Reloading Powder Feature.
There has been a hue and cry on some internet sites about changes in smokeless powder classifications by the Federal Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF). Writers have been concerned that recent interpretations by the ATF would make it much more difficult to store and transport reloading powders, which in turn could lead to price increases and/or powder shortages. Concern arose over the potential re-classification of “wetted” Nitrocellulose as a “high explosive”. Since “high explosives” are subject to more stringent rules, such re-classification would alter the way common smokeless propellants could be lawfully stored and transported.
Thankfully, there is good news. On August 31st the ATF issued an Addendum to its June 16 ATF Explosives Industry Newsletter saying that its policies regarding smokeless powders containing Nitrocellulose will not change… at least for now:
Based on this “Addendum”, it seems the ATF has tabled its proposal to classify Nitrocellulose-based smokeless powders as “high explosives”.
The NRA Institute for Legislative Action (NRA ILA) confirms that the ATF has backed off, so that current practices for powder storage and transport can continue unchanged. Thus hand-loaders should NOT face an impending powder shortage and/or price hikes. Here is the NRA ILA’s report:
ATF Delays Any Changes to Nitrocellulose Regulation
Earlier this summer, ATF released an Explosives Industry Newsletter that changed the agency’s treatment of nitrocellulose, the primary component in smokeless powders used in modern ammunition. This change had the potential to seriously disrupt ammunition supply in the United States because it changed a long-standing ATF policy that exempted properly “wetted” nitrocellulose from treatment as an explosive under federal law.
NRA and [shooting industry representatives] raised these concerns to ATF and any change in ATF’s treatment of nitrocellulose is now officially delayed. In an addendum to the earlier newsletter, ATF announced that it “will conduct further industry outreach concerning wetted Nitrocellulose. In the interim, previously authorized industry practices concerning wetted Nitrocellulose will NOT be affected.”
While the addendum doesn’t indicate that ATF has permanently abandoned this change to nitrocellulose regulation, smokeless powder manufacturers will be permitted to continue normal operation, at least for the time being. NRA will continue to work to ensure that any future change to nitrocellulose regulation will not affect ammunition supply.
ATF Industry Newsletter Caused Concern
The cause for firearms industry concern was the ATF’s statement about Nitrocellulose published in the June 2016 ATF Explosives Industry Newsletter. The key language is shown in the right column below. According to the NRA ILA, the ATF has, at least for the time being, decided NOT to change its policies regarding the storage and transport of “wetted” Nitrocellulose. Accordingly, “smokeless powder manufacturers will be permitted to continue normal operation”.
August 26th, 2016
John Whidden of Whidden Gunworks used the .243 Winchester cartridge to win the 2016 NRA Long Range Championship, his fourth LR title at Camp Perry. John selected the .243 Win because it offers excellent ballistics with manageable recoil. John says that, at least for a sling shooter, the .243 Win is hard to beat at long range. Yes, John says, you can get somewhat better ballistics with a .284 Win or .300 WSM, but you’ll pay a heavy price in increased recoil.
.243 Winchester — The Forgotten 6mm Cartridge for Long Range
by John Whidden, 2016 National Long Range Champion
My experience with the .243 cartridge for use as a Long Range High Power cartridge dates back about 10 years or so. After building a .300 WSM, I realized that the recoil was hurting the quality of my shots. The WSM shot great, but I couldn’t always execute good shots when shooting it. From here I built a 6.5-284, and it shot well. I also had a very accurate 6mmBR at the time, and my logic in going to the .243 Win was to get wind performance equal to the 6.5-284 with recoil similar to the 6mmBR. The experiment has worked out well indeed!
Championship-Winning Load: Berger Bullets, Lapua Brass, and Vihtavuori N160
For a load, currently I’m shooting Lapua brass, PMC primers (Russian, similar to Wolf), VihtaVuori N160 single-base powder, and Berger 105 grain Hybrid bullets. I switched to the Hybrid bullets fairly recently at the beginning of the 2015 season. Previously I shot the 105gr Berger hunting VLDs, and in testing I found that the Hybrids were just as accurate without having to seat the bullet into the lands. The velocity of this combination when shot through the excellent Bartlein 5R barrels (32” length) is around 3275 FPS.
For my match ammo, I seat the Berger 105 Hybrids well off the lands — my bullets are “jumping” from .035″-.060″. I only use one seating depth for ammunition for multiple guns (I know some benchrest shooters will stop reading right here!) and the bullets jump further in the worn barrels than in the fresh barrels. The bullets are pointed up in our Bullet Pointing Die System and are moly-coated. The moly (molybdenum disulfide) does extend the cleaning interval a little bit, probably 20% or so. The Lapua .243 Win brass is all neck-turned to .0125″ thickness.
Whidden’s .243 Win Ammo is Loaded on a Dillon
My loading process is different than many people expect. I load my ammo on a Dillon 650 progressive press using our own Whidden Gunworks dies. However powder charges are individually weighed with a stand-alone automated scale/trickler system from AutoTrickler.com (see below). Employing a high-end force restoration scale, this micro-processor controlled system offers single-kernel precision. The weighed charges are then dropped into the cases with a funnel mounted to the Dillon head.
The Lapua .243 Win brass is full-length sized every time, and I run one of our custom-sized expanders in my sizer die. The expander measures .243″ which yields the desired .001″ neck tension. In my experience, the best way to get consistent neck tension is to run an expander in the case neck at some point. When sizing the case neck by a minimal amount such as is the case here, I don’t find any negative points in using an expander in the sizer die.
In my experience, the keys to accurate long range ammo are top quality bullets and the most consistent neck tension you can produce. From these starting points, the use of quality components and accurate powder measurement will finish out the magic.
Great Ballistics with 6mm 105s at 3275 FPS
Running at an impressive 3275 FPS, Berger 6mm 105 grain Hybrids deliver ballistics that are hard to beat, according to John Whidden:
“My .243 Win shoots inside a 6.5-284 with 142-grainers. Nothing out there is really ahead of [the .243], in 1000-yard ballistics unless you get into the short magnums or .284s and those carry a very significant recoil penalty. In the past I did shoot the 6.5-284. I went to the .243 Win because it had similar ballistics but had much less recoil. It doesn’t beat me up as much and is not as fatiguing.
With the .243 Win, there’s no tensing-up, no anticipating. With the reduced recoil (compared to a 7mm or big .308), I can break and shoot very good quality shots. I find I just shoot better shots with the .243 than I ever did with the 6.5-284.”
August 24th, 2016
In this .308 Win test, 70° F ammo shot 96 FPS slower than ammo heated to 130.5° F. And the 130.5° ammo was 145 fps faster than ammo right out of the freezer (at 25.5° F). That’s a huge difference…
EDITOR’s NOTE: The Sierra tester does not reveal the brand of powder tested here. Some powders are much more temp sensitive than others. Accordingly, you cannot extrapolate test results from one propellant to another. Nonetheless, it is interesting to see the actual recorded velocity shift with ammo temperature variations in a .308 Win.
Written by Sierra Chief Ballistician Tommy Todd
This story originally appeared in the Sierra Bullets Blog
A few weeks ago I was attending the Missouri State F-Class Match. This was a two-day event during the summer and temperatures were hot one day and hotter the next. I shot next to a gentleman who was relatively new to the sport. He was shooting a basically factory rifle and was enjoying himself with the exception that his scores were not as good as he hoped they would be and he was experiencing pressure issues with his ammunition. I noticed that he was having to force the bolt open on a couple of rounds. During a break, I visited with him and offered a couple of suggestions which helped his situation somewhat and he was able to finish the match without major issues.
He was shooting factory ammunition, which is normally loaded to upper levels of allowable pressures. While this ammunition showed no problems during “normal” testing, it was definitely showing issues during a 20-round string of fire in the temperatures we were competing in. My first suggestion was that he keep his ammunition out of the direct sun and shade it as much as possible. My second suggestion was to not close the bolt on a cartridge until he was ready to fire. He had his ammo in the direct sunlight and was chambering a round while waiting on the target to be pulled and scored which can take from a few seconds to almost a minute sometimes.
This time frame allowed the bullet and powder to absorb chamber [heat] and build pressure/velocity above normal conditions. Making my recommended changes lowered the pressures enough for the rifle and cartridge to function normally.
Testing Effects of Ammunition Temperature on Velocity and POI
After thinking about this situation, I decided to perform a test in the Sierra Bullets underground range to see what temperature changes will do to a rifle/cartridge combination. I acquired thirty consecutive .30 caliber 175 grain MatchKing bullets #2275 right off one of our bullet assembly presses and loaded them into .308 Winchester ammunition. I utilized an unnamed powder manufacturer’s product that is appropriate for the .308 Winchester cartridge. This load is not at the maximum for this cartridge, but it gives consistent velocities and accuracy for testing.
I took ten of the cartridges and placed them in a freezer to condition.
I set ten of them on my loading bench, and since it was cool and cloudy the day I performed this test I utilized a floodlight and stand to simulate ammunition being heated in the sun.
I kept track of the temperatures of the three ammunition samples with a non-contact laser thermometer.
The rifle was fired at room temperature (70 degrees) with all three sets of ammunition. I fired this test at 200 yards out of a return-to-battery machine rest. The aiming point was a leveled line drawn on a sheet of paper. I fired one group with the scope aimed at the line and then moved the aiming point across the paper from left to right for the subsequent groups.
NOTE that the velocity increased as the temperature of the ammunition did.
The ammunition from the freezer shot at 2451 fps.
The room temperature ammunition shot at 2500 fps.
The heated ammunition shot at 2596 fps.
The tune window of the particular rifle is fairly wide as is shown by the accuracy of the three pressure/velocity levels and good accuracy was achieved across the board. However, notice the point of impact shift with the third group? There is enough shift at 200 yards to cause a miss if you were shooting a target or animal at longer ranges. While the pressure and velocities changed this load was far enough from maximum that perceived over pressure issues such as flattened primer, ejector marks on the case head, or sticky extraction did not appear. If you load to maximum and then subject your ammunition to this test your results will probably be magnified in comparison.
This test showed that pressures, velocities, and point-of-impact can be affected by temperatures of your ammunition at the time of firing. It’s really not a bad idea to test in the conditions that you plan on utilizing the ammo/firearm in if at all possible. It wouldn’t be a bad idea to also test to see what condition changes do to your particular gun and ammunition combination so that you can make allowances as needed. Any personal testing along these lines should be done with caution as some powder and cartridge combination could become unsafe with relatively small changes in conditions.
August 22nd, 2016
At the request of our readers, we provide select “Deals of the Week”. Every Monday morning we offer our Bargain selections. Here are some of the best deals on firearms, hardware, reloading components, 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.
1. Kelbly.com — 15% Off Discount on All Products
Looking for a Panda or Atlas Action, or a complete match rifle? Here’s a great promotion from our friends at Kelbly’s. Now through Tuesday, August 23, 2016 you can get 15% of ANYthing on the Kelblys.com website. That includes rifles, actions, stocks, barrels, scope rings, muzzle brakes, Berger bullets, accessories and more. To save big, use code 15ALL at checkout. Don’t delay — this offer expires at 11:59 pm on September 1, 2016.
2. EuroOptic.com — Tikka T3 Liquidation Sale, Huge Discounts
Looking for a great price on an excellent hunting rifle? Here is the Tikka Deal of the Decade. EuroOptic.com has received nearly 3,500 Tikka T3 rifles, which will be sold at deep discounts as part of an inventory clearance program by Beretta, Tikka’s parent company. The Tikka T3 is a good, stout rifle with a smooth, 3-lug action, crisp trigger, and quality barrel. Accuracy is typically well under 1 MOA (for three shots). T3 barreled actions also are a good “core” for a tactical build. The strong T3 action handles detachable magazines, and fits a variety of third-party stocks.
3. Monmouth — Hornady 6.5 Creedmoor Brass, $34.95 for 50
The 6.5 Creedmoor has become one of the most popular chamberings for tactical/practical shooting. This mid-sized cartridge offers excellent ballistic performance with 120-140gr bullets, with moderate recoil and excellent inherent accuracy. Now you can get Hornady-brand 6.5 Creedmoor brass at a very good price: $34.95 for 50 cases (that’s $69.90 per 100).
4. Amazon — Kowa 60mm TSN-601 Spotting Scope Body, $259.00
If you are looking for a rugged, reliable, and affordable spotting scope to watch flags, mirage, and shot spotting discs, this angled-body Kowa TSN-61 will do the job. And $259.00 with free, fast Prime Shipping is a great deal. These Kowa spotters have been used successfully for years by prone and High Power competitors. Sure the glass can’t rival the latest top-of-the-line HD spotting scopes, but the TSN-61 is a small fraction of the price of high-end models which cost $2000 or more. The money you save can buy four premium hand-lapped barrels. NOTE: Eyepieces are sold separately — expect to pay $275.00 – $300.00 for a Kowa 20-60X Zoom eyepiece.
5. Midsouth — $15.00 HazMat Fee with 15-lb Powder Purchase
When you purchase powder, it makes sense to buy in bulk. That way you get powder from the same lot, and save on the HazMat fees. Now you have even more incentive to place a big order. Right now Midsouth is offering $15.00 Hazmat with orders of 15 or more pounds of powder. Get 15 one-pounders or two eight-pound jugs and you’ll qualify. Midsouth has a large selection of popular powders in stock, including Hodgdon Varget, H4198, H48931sc, and the new IMR Enduron powders. With this special HazMat deal you can save up to $20.00 (many vendors charge $35.00 HazMat per order). Don’t hesitate — this offer ends 8/25/2016.
6. Amazon — Tipton Gun Vise, $30.32 (free Prime Shipping)
This is an awesome deal on a durable, well-designed polymer Gun Vise that every rifle owner can use. Your Editor has one of these units which has served well for more than a decade. The base has compartments for solvents, patches, and tools. The cradles and pads contacting your gunstock are a soft, rubber-like material that is gentle on fine finishes. This vise is relatively light in weight, but sturdy enough to support big, heavy rifles.
7. Amazon — Mildot Master Ballistics Calculator, $29.86
A Mildot Master is one item every tactical/practical shooter should own. This handy tool has been used successfully for years. It doesn’t require batteries, no keypad data entry is require through a keypad is necessary, as the device is purely analog. No complex calculations for determination of telescopic sight adjustment or hold-over at various ranges are necessary, as the scales of the device convert drop/drift figures directly into both MOA and mils.
8. Amazon — Ten-Pack of 2″-Diameter Splatter Targets, $8.99
We use these splatter targets for fun shoots and practice at 300 and 400 yards. When hit, each shot displays as a bright, neon-green/yellow circle. That makes it easy to spot your shots, even with relatively low-power optics. These targets also work great for handgun practice at shorter distances. For just $8.99 you get ten sheets each with 16 stick-on circles — a total of 160 target bulls.
August 19th, 2016
Here’s an important announcement for anyone who uses a powder in the 4350 range. Alliant is now shipping the all-new Reloder 16 powder. The burn rate is slightly faster than Reloder 17, and a bit slower than Varget or Reloder 15. Notably, this new Reloder 16 powder is very temp stable. AccurateShooter.com was shown “top secret” test results comparing Reloder 16 with other popular propellants, including Hodgdon Extreme series powders. The results for Reloder 16 were remarkable. Reloder 16 showed extremely constant velocities even with very high ambient temps — so this is a powder you can shoot even on hot Arizona summer days.
CLICK HERE for Reloder 16 Suggested Load Recipes
This is NOT just a slower version of Alliant’s double-based Reloder 15 (which words great in the 6mmBR and Dasher cartridges). Reloder 16 is a completely new formulation, produced in Sweden by Bofors for Alliant. Reloder 16 utilizes TZ technology, which manipulates the response of the propellant and resists the natural tendency to generate more pressure at higher temperatures and less pressure at lower temperatures.
As a result, Reloder 16 offers outstanding temperature stability. Based on the test results we’ve seen, if you are using H4350 or IMR 4451 currently, you should definitely give Reloder 16 a try. The powder also boasts excellent lot-to-lot consistency and contains a proprietary de-coppering additive.
Match and Hunting Cartridge Applications:
Alliant tells us that Reloader 16 “is ideal for traditional hunting cartridges, such as .30-06 Springfield and .270 Winchester, as well as 6.5mm target loads and tactical applications wherein temperature stability is required.” We also think the powder may work very well in these popular match cartridges: 6XC, .243 Win, 6.5×47 Lapua, 6.5 Creedmoor, .260 Rem, .284 Win, and .300 WSM. For example, Alliant’s Load Data Sheet shows a 2772 FPS load with 142gr SMKs in the .260 Rem.
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