Quick question on br4 vs 400s...

[Rsadams]

Since I had problems with cci 400 SR primers flattening with even a medium load as been discussed here...I have bought a brick of br4 to go with a thousand hornady 55gr fmj-bt projectiles I have been saving for a shtf time..

My question is can I use load data for the 400s with the br4s or should I ladder test them? Will they be hotter, not as hot or the same as the standard 400s? I normally ladder test starting low or even in the middle of the book and work my way up.. But I will be starting in .223 load data and working up to about a start load for 5.56.

Just some info.. Somewhere around 24.5gr of TAC from a 5.56 AR chamber. Is were I would like to end up. I started at 23.1 everything ok but when I jumped to 23.5 it slightly flattened some but not all 400s. the hornady manual list 23.9 as max for .223 but in comparison the ramshot data says that's a starting load.. You know how that goes.

You know what, I'll start at 23.5 and work up becouse thats unknown territory..but with the br4 should I start over at 23.1 or can I just pick up were I left off at 23.5 ? Any further info you may need , if any just ask..

Thanks, shawn

 

[chkunz]

It would be helpful to know more about you application and your expectations.

For some applications the change in primers you are considering is not as important as other things. There are two main considerations in your question, accuracy and safety.

As to safety, when working above the listed max loads, changing primers is more significant than when working below those loads, elementary. The limitations of listed max loads has been discussed at length but still you are in that zone.

My understanding is that the CCI 400s and the BR-4s differ in quality and not energy, for starters it would be helpful if someone can confirm that.

 

[dkhunt14]

It would be helpful to know more about you application and your expectations.

For some applications the change in primers you are considering is not as important as other things. There are two main considerations in your question, accuracy and safety.

As to safety, when working above the listed max loads, changing primers is more significant than when working below those loads, elementary. The limitations of listed max loads has been discussed at length but still you are in that zone.

My understanding is that the CCI 400s and the BR-4s differ in quality and not energy, for starters it would be helpful if someone can confirm that.

The BR4 is a match primer and has a thicker cup. The ingredients may be close and maybe not. Matt

 

[chkunz]

Quoted above, "The BR4 is a match primer and has a thicker cup. The ingredients may be close and maybe not. Matt"

Probably worth asking CCI, this is significant to your question and they know the answer.

 

[Rsadams]

Quoted above, "The BR4 is a match primer and has a thicker cup. The ingredients may be close and maybe not. Matt"

Probably worth asking CCI, this is significant to your question and they know the answer.

Ok thanks guys.....

 

[RonAKA]

My question is can I use load data for the 400s with the br4s or should I ladder test them?

The basic difference between the BR-4 and the 400 is the thickness of the cup metal, and the BR-4's are produced with better quality control. A ladder test is done to determine the best velocity for your barrel. There is no point in redoing a ladder test. Just load a few and target the same velocity if you were happy with what you were getting for accuracy. A total ladder test is a waste of time. Just chronograph the velocity and adjust as required.

 

[500Stroker]

Shoot a powder ladder with the BR-4's takes all the guess work out of it.
Good luck