June 25th, 2020

Quest for Less Vertical — Six Primer Types Tested at 500 Yards

primer 500 yard testing node vertical H4895 BRA

Do primer types make a significant difference in accuracy or vertical dispersion at long range? The answer is “maybe”. Here’s one anecdotal study that tracked vertical variance among six different primer types. The tester is a good shooter with a very accurate rifle — four of the six 4-shot groups were under 2″ at 500 yards. This test doesn’t settle the question, but does suggest that it may be worth trying a few different primer types with your match ammo.

Here is a very interesting test for the 6 BRA (6mmBR Ackley) cartridge. Forum member James Phillips, a talented long-range benchrest shooter, tested SIX different primer types from three different manufacturers. To help determine vertical dispersion, James set his target out at 500 yards. He then proceeded to shoot 4-shot groups, in order, with each primer type. Velocities were recorded with a chrono. The photo above shows the results. James says: “I’ll retest the best two for accuracy and consistency with 10 shots each”. CLICK HERE for full-screen target photo.

Wheeler 6BR 6mmBR Ackley Improved James Phillips

As you can see, ALL the groups are pretty impressive. The smallest groups, 1.253″, was shot with CCI 400 primers. Next best (and very close) was CCI BR4, at 1.275″ for four shots. The “flat line” winner was the Remington 7.5, at upper left. There was almost no vertical. If you are intrigued by this interesting primer test, you can ask join the discussion in this Primer Test FORUM THREAD.

Primer Brand Group Size Velocity Extreme Spread Std Deviation
Remington 7.5 1.985″ 4 shot 2955 FPS 8 FPS 4.0 FPS
Federal 205M 2.200″ 4 shot 2951 FPS 11 FPS 4.8 FPS
Sellier Bellot SR 1.673″ 4 shot 2950 FPS 14 FPS 5.9 FPS
CCI 450M 2.341″ 4 shot 2947 FPS 14 FPS 6.6 FPS
CCI 400 1.253″ 4 shot 2950 FPS 3 FPS 1.3 FPS
CCI BR4 1.275″ 4 shot 2949 FPS 15 FPS 6.9 FPS

CARTRIDGE: 6mmBR Ackley, aka 6 BRA. Parent case is 6mmBR Norma. The 6 BRA is fire-formed to create a 40-degree shoulder and less body taper. Capacity is increased, but the neck is longer than a 6mm Dasher. The capacity is enough to get to the 2950+ FPS accuracy node. Some shooters say the 6 BRA is more forgiving than the 6mm Dasher. The 6 BRA is certainly easier to fire-form.

LOAD SPEC: 6 BRA (40° 6 BR Improved), 31.1 grains Hodgdon H4895, Bart’s 105gr “Hammer” bullets.

TEST REPORT — Conditions, Shooting Method, Loading Method

Tester James Phillips posted this report in our Shooters’ Forum:
Conditions: The testing was done in the morning over flags. The flags never moved or even twitched. I had as perfect conditions as I could have asked for. It was overcast so no mirage and no wind. There were no other shooters, just me.

Test Procedure: Each shot was precisely shot at my pace and centered the best possible using my Nightforce 15-55X scope. I did not use the round-robin method. Each four-shot group with the same was shot at one time. Then I moved onto the next primer. Everything felt right for each and every shot fired today. Of course I could repeat the test tomorrow and it could be exact opposite of today’s test. We can chase this forever. But [soon] I’m going to test the BR4 and 400 primer… for best accuracy and consistency for 10 shots each.

How Rounds Were Loaded: Each load was weighed to one (1) kernel of powder. So I know that’s as good as I can weigh them. Each bullet seating force was within 1# on my 21st Century hydraulic arbor press.

Previous Initial Load Testing: All groups were shot with 31.1 grains of H4895. During initial load testing I settled in on the Sellier & Bellot primer to finalize everything as it showed more promise over the CCI 450 Magnum I also tried. I was actually surprised to have seen the higher ES and SD from that primer today along with the vertical shown. [Editor: Look carefully — one shot from the CCI 450 is right in the center black diamond, stretching the vertical. By contrast the Rem 7.5 had almost no vertical.]

primer 500 yard testing node vertical H4895 BRA

Velocity and NODE Considerations: I was about 5-6 FPS above what appeared to been my optimum velocity of 2943-2945 FPS, so I’ll test 5 shots of 31.0 and 5 of 31.1 and see what happens from there. I can only assume my velocities where higher due to the higher humidity and of course temps were 5 degrees warmer this morning as well. It wasn’t far off but I noticed it.

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April 27th, 2020

Bargain Finder 240: AccurateShooter’s Deals of the Week

AccurateShooter Deals of the Week Weekly Bargain Finder Sale Discount Savings

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.

1. Camera Land — Kestrel Sportsman Weather Meter, $249.99

kestrel wind meter

All shooters need accurate wind velocity and direction info. One of the best wind tools is the Kestrel. Forum member Knotwild found an amazing deal on the excellent Kestrel Sportsman Ballistics Weather Meter. This unit features the enhanced Applied Ballistics G1/G7 solver, including Aerodynamic Jump, Spin Drift, and Coriolis corrections for accurate long-range shots. Grab the Kestrel Sportsman for just $249.99. This same Kestrel Sportsman costs up to $500 elsewhere.

2. MidwayUSA — Swarovski – Kahles Demo & Refurbished Sale

Swarovski - Kahles Demo & Refurbished sale

Swarovski and Kahles scopes are often considered top-of-the-line but are rarely found at a discount. Head over to MidwayUSA and check out the Swarovski & Kahles Demo and Refurbished Sale. There’s a great selection of rifle optics and spotting scopes for just about every discipline. If you’re looking to save serious $$ on top-notch glass for that new rig you’re building, here’s your chance.

3. Amazon — BOG DeathGrip Tripod, $124.99

BOG DeathGrip Tripod

Whether out in the field, at the range or shooting a PRS match, keeping your rifle stable in varying conditions is a must. If you’re tired of carrying a monopod and bags around, here’s your chance to replace them with something more practical and functional. Grab the BOG DeathGrip Tripod and you’ll have a stable platform to shoot from any position. It features a 3-position leg lock for use in prone, kneeling, sitting and standing positions. This stable shooting platform features an adjustment knob that controls up to 50 degrees of tilt and a clamping head that pans 360 degrees with tension adjustment.

4. Bruno Shooters Supply — Savage Action Sale

savage action sale

Many shooters want a custom gun but balk at the $1000+ cost of a custom action. They may settle for factory Rem 700 action but forget about Savage. Savage makes a really solid action on which you can build a very accurate varmint or match rifle. The founder of this site shot a Savage-action 6BR at 600-yard steel matches for many years. With a Pac-Nor barrel, that Poor Man’s Hammer 6BR delivered solid quarter-MOA accuracy and held a range record for many years. For a good price on a Savage Match action complete with trigger, check out Bruno’s Savage action sale.

5. Natchez and Midsouth– RCBS Reloading Kit Sale

rcbs press sale

Given pandemic concerns, many folks have decided to start loading ammo in larger quantities. For those just getting started in reloading, here are two excellent kits from RCBS. The RCBS AR Tactical Reloading Kit offers their Reloader Special 5 press and even comes with AR Series Dies: 5.56/.223, .308/7.62, .300 AAC Blackout, 7.62×39. Or you can choose the Rock Chucker Supreme Master Reloading Kit if you’re looking for a stronger press and more commonly sought-after accessories. Either way these are excellent starter kits, offering great value for money.

6. Midsouth Shooters — Lee APP Press, $54.88

lee app press sale

Sorry folks — this was such a great deal, the Lee APP Press sold out on Monday. However, the Deluxe version of the APP press, which includes a case-feeder, is still available for $75.49. The Deluxe APP Press features an innovative case/bullet feeder with Jaws that automatically open and grasp the bullet or case and move then into operating position.

Processing brass is a necessary evil in the reloading world. Many processing chores are best done with a dedicated press, but that can get expensive. Lee saw the need for a inexpensive yet efficient processing press and brought out the Lee APP Automatic Processing Press. This can efficiently handle tasks such as decapping, case sizing, and primer pocket swagging. Here are two videos that show how this unique Lee APP press operates.

7. Amazon — Frankford Arsenal Vibra Prime, $56.19

vibra prime

Filling primer tubes can be time consuming and hard on the hands. If you’re looking to fill those tube faster and with less effort check out the Frankford Arsenal Vibra Prime. With the ability to fill just about any brand of tube in less than one minute, this is a great time saver. This editor uses this tool all the time — and considers it a “must have” for every reloading bench.

8. Powder Valley — CCI & Federal Rifle Primers

rifle primers

Reloading components have been a tough to find commodity lately especially primers. If you’re on the hunt for standard or magnum rifle primers we found CCI 450 Small Rifle Magnum primers as well as the Federal GM205M Small Rifle MatchGrade primers at Powder Valley and with a limit of 5 per person that’ll still get you more than enough primers for the rest of the year. Powder Valley also has large rifle primers in stock at good prices.

9. CDNN Sports — Taurus Spectrum .380 ACP, $179.99

rifle primers

Here’s a very compact, easy-to-conceal carry gun that can fit in pants pockets and small purses. All edges are smooth and rounded for ease of carry, with minimal “printing”. These Taurus Spectrum .380 ACPs are available in four color combos: Black/gray, Black/tan, Black/green, and a stylish White/blue/gray combo. We tried these pistols at SHOT Show. They are comfortable in the hand and the trigger is decent. Right now this Taurus Spectrum pistol is just $179.99 at CDNN Sports, making it one of the least expensive handguns on the market.

10. Graf and Sons — Hinged Rifle Ammo Box Sale

rifle ammo box

It can be hard to find good compact ammo boxes for rifle ammo loaded with long match bullets. We like these Frankford Arsenal 50-round and 100-round hinged rifle ammo boxes. These are slightly taller than most plastic ammo boxes, so they are better suited for longer, match-length ammo. These Frankford boxes hold match ammo securely without taking up a lot of space like the big, green ammo carriers with handles.

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February 13th, 2020

Primers and Pressure Tolerances — How Primers Vary

Primer Pressure signs

by James Calhoon
(First Printed in Varmint Hunter Magazine, October, 1995)

Primers and Pressures

In the course of talking to many shooters, it has become clear to me that the manufacturers of primers have done a less than adequate job of educating reloaders on the application of their primers. Everybody seems to realize that some primers are “hotter” than others and some seem to shoot better for them than others, but few reloaders know that primers have different pressure tolerances.

Primer Pressure Tolerance
When loading a .223 to the maximum, I was getting primer piercing before I reached case overloading. I don’t know what prompted me to try CCI 450s instead of the 400s which I had been using, but I did. Presto! No more piercing! Interesting!? A primer that has a hotter ignition and yet withstands more pressure! Thats when I decided that it was time to do a dissection of all primers concerned. The chart below shows my results.

Primers and Pressures
NOTE: These primer dimensions were measured many years ago. There may be some differences in current production specifications.

By studying the numbers (Cup “A” thickness), one can see which primers in the small rifle sections should be more resistant to primer cratering and/or piercing. Primer cup diameters are all similar and appear to follow a specification, but check out the cup thickness in the small rifle primers (Dimension “A”). Some cups are quite a bit thicker than others: .025″ for CCI 450 vs. .0019″ for Fed 200. Large rifle primers all appear to have the same cup thickness, no matter what the type. (As a note of interest, small pistol primers are .017″ thick and large pistol primers are .020″ thick.)

If you are shooting a 22 Cooper, Hornet, or a Bee, the .020″ cup will perform admirably. But try using the .020″ cup in a 17 Remington and you will pierce primers, even with moderate loads.

Considering that cup thickness varies in the small rifle primers, it is obvious that primer “flatness” cannot solely be used as a pressure indicator.

Another factor which determines the strength of a primer cup is the work-hardened state of the metal used to make the primer cup. Most primers are made with cartridge brass (70% copper, 30% zinc), which can vary from 46,000 psi, soft, to 76,000 psi tensile strength when fully hardened. Note that manufacturers specify the hardness of metal desired, so some cups are definitely “harder” that others.

What does all this mean to the reloader?
- Cases that utilize small rifle primers and operate at moderate pressures (40,000 psi) can use CCI 400, Federal 200, Rem 6 1/2, or Win SR. Such cases include 22 CCM, 22 Hornet and the 218 Bee. Other cases that use the small rifle primer can use the above primers only if moderate loads are used. Keep to the lower end of reloading recommendations.

– Cases that utilize small rifle primers and operate at higher pressures (55,000 psi) should use CCI 450, CCI BR4, Fed 205 and Rem 7 1/2.

– All the large rifle primers measured have the same thickness. Therefore choose based on other factors, such as accuracy, low ES/SD, cost, cup hardness, and uniformity.

Hope this clears up some primer confusion. If you want more information about primers, priming compounds, or even how to make primers, the NRA sells an excellent book called “Ammunition Making” by George Frost. This book tells it like it is in the ammo making industry.

Jim Calhoon Products

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September 3rd, 2011

Bruno’s Offers Free Hazmat on 10K Orders of Federal Primers

Free Haz-Mat — that’s right, for a limited time, Bruno Shooters Supply is offering Free Haz-Mat if you purchase at least 10,000 primers (that’s ten 1,000-ct boxes). Bruno’s website states: “We will pay the Hazardous-Materials fee of $25.00 on orders of any 10,000 primers from the below list up to 50 pounds. You may mix and match. Each 1,000 primers weighs approximately one pound. You may also include powder at the regular price to reach your 50-pound weight limit. Shipping charges are additional. Haz-Mat orders ship via FedEx ground and a signature will be required. Offer applies to in-stock items only. No backorders. One offer per order. Please call (623) 587-7641 if you have any questions or concerns before placing your order.”

Bruno Shooters Supply Primer Sale

Story tip by EdLongrange. We welcome reader submissions.
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