CCI #41 vs. BR-4 primers... which is more consistent?

[JimmyT]

I'm looking to squeeze as much accuracy out of my 18" and 16" ARs that I can get.

I'm looking for anyone with experience with BR-4 primers in 5.56 pressure ammo. I am loading 77 grain CC and SMK in LC cases over 24.3 grains of TAC or 23.4 grains of 8208XBR. I'm going out Saturday to try this out.

I was using the #41 to avoid the chance of slam fires in my ARs, but is it necessary with high quality parts?

Any replies will bee appreciated.

 

[Longshot85]

I'm looking to squeeze as much accuracy out of my 18" and 16" ARs that I can get.

I'm looking for anyone with experience with BR-4 primers in 5.56 pressure ammo. I am loading 77 grain CC and SMK in LC cases over 24.3 grains of TAC or 23.4 grains of 8208XBR. I'm going out Saturday to try this out.

I was using the #41 to avoid the chance of slam fires in my ARs, but is it necessary with high quality parts?

Any replies will bee appreciated.

I haven't used the 41's but here's some BR-4 data

Unknown brass (most likely from American eagle)
CCI Br-4
XBR 8208
77 TMK

Rifle is a WOA SPR 18 inch, suppressed, JP SCS...etc....

 

[Bantam1]

My data showed the 41 to be a little hotter primer than the BR-4. It was identical to the 450's I have tried, but with a harder cup. The BR-4 gives me the same velocity as the 400. I do get a little lower SD with the BR primers. I tested them in my 556 loads but now use them for my 65CM.

I use 8208 for my 556 loads and my magic load likes the Fed GMM primer. Sub MOA and an SD of 3 and 10 ES. Across 50 rounds the SD went up to 4.1 and ES to 13 or 14 if my memory is correct. I gave up some velocity for consistency.

 

[Nimothy]

I shoot 205m in everything I care about and 400’s in all the sbr 556 300bo stuff. I bought a couple bricks of br4 and 450’s at the same time, they were giving me fits (not going off) across 4 different cartridges, I switched the federal and my es’s dropped a few FPs and my problems went away.

 

[nn8734]

I have found Remington 7 1/2 primers to give me a little more velocity, tighter groups and lower SDs than the CCI41s across two of my ARs (DDm4a1 and Mk18 mod1). Working on a load for my Mod H where I’ll be comparing those two primers and Federal 205Ms but won’t know how that turns out until next weekend at the earliest. I use LC brass exclusively.