April 6th, 2019

Primer Comparison Testing with 6 BRA at 500 Yards

primer 500 yard testing node vertical H4895 BRA

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 6th, 2019

President Trump Will Headline NRA Convention April 26, 2019

NRA Annual Meetings and Exhibits POTUS President Trump Convention Indiana FREE Mobile App

President Donald Trump will address NRA members at the NRA-ILA Leadership Forum on Friday, April 26, 2019 in Indianapolis, Indiana. This is the third consecutive year that President Trump will deliver the keynote address at the Leadership Forum. This is part of the NRA Annual Meetings & Exhibits, which runs April 25-28 at the Indiana Convention Center in Indianapolis.

“Donald Trump is the most enthusiastic supporter of the Second Amendment to occupy the Oval Office in our lifetimes. It is truly an honor to have President Trump address NRA members for the fifth consecutive year,” said Chris Cox, NRA-ILA Executive Director. “President Trump’s Supreme Court [and Appellate Court] appointments ensure that the Second Amendment will be respected for generations to come. Our members are excited to hear him speak and thank him for his support for our Right to Keep and Bear Arms.”

President Donald Trump
Keynote Speaker, NRA-ILA Leadership Forum
TICKETS HERE: bit.ly/NRAILALeadershipForum
WHERE:
Indiana Convention Center—Lucas Oil Stadium
100 South Capitol Avenue
Indianapolis, Indiana 46255
WHEN:
Friday, April 26, 2019
11:00 am – 4:00 pm
Tickets Required

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NRA Annual Meetings and Exhibits POTUS President Trump Convention Indiana FREE Mobile App

If you plan to attend the 2019 NRA Annual Meetings & Exhibits, you should get the official Mobile APP. This will help you access Convention info quickly and easily. You can search for exhibitors, tag your favorites, request meetings, add notes, and map booth locations. Key APP features include: Event Floorplan, Searchable Directory of Exhibitors, Event and Seminar Schedule, New Products Info with Product Photos.

From your mobile device, click buttons for official NRA Meetings mobile APP:

NRA convention app
Click HERE for iOS APP
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Click HERE for Android APP

Not on your mobile device? Click HERE to send yourself an access link.

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