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Jimro · June 29, 2013, 02:19 AM

With an AR there is a small measure of built in safety against an out of battery event as the firing pin can't hit the primer until the bolt face has at least partially rotated. With rifles based on the Garand action, (Garand, M1A, Mini-14/30) that isn't the case.

I wouldn't want to experience a slam fire even in any rifle, but a full OOB slamfire scares the crap out of me. I have used CCI 400's for AR reloads, but I stopped and transitioned to Wolf Milspec Primers (after trying out the CCI 41s and finding the wolf does the same job cheaper).

CCI 400's are not recommended for full house 223/5.56 loads because of pressure. CCI 400's are meant for things like 22 Hornet and other lower pressure rifle cartridges, and according to CCI are the same as small magnum pistol primers (which simplifies loading small magnum pistol rounds for me). That many people use them for feeding AR's doesn't mean that they are "safe" to use for that purpose, just that some people have done it and experienced no negative results. I have confidence that the CCI recommended usage guidelines are well within the "margin of stupid" for over engineering a primer and are unlikely to pierce even with a full house 223 load, but that you get a better margin by using milspec or CCI 450 primers for that application.

Jimro

June 29, 2013, 02:19 AM	#16
Jimro Senior Member Join Date: October 18, 2006 Posts: 7,097	With an AR there is a small measure of built in safety against an out of battery event as the firing pin can't hit the primer until the bolt face has at least partially rotated. With rifles based on the Garand action, (Garand, M1A, Mini-14/30) that isn't the case. I wouldn't want to experience a slam fire even in any rifle, but a full OOB slamfire scares the crap out of me. I have used CCI 400's for AR reloads, but I stopped and transitioned to Wolf Milspec Primers (after trying out the CCI 41s and finding the wolf does the same job cheaper). CCI 400's are not recommended for full house 223/5.56 loads because of pressure. CCI 400's are meant for things like 22 Hornet and other lower pressure rifle cartridges, and according to CCI are the same as small magnum pistol primers (which simplifies loading small magnum pistol rounds for me). That many people use them for feeding AR's doesn't mean that they are "safe" to use for that purpose, just that some people have done it and experienced no negative results. I have confidence that the CCI recommended usage guidelines are well within the "margin of stupid" for over engineering a primer and are unlikely to pierce even with a full house 223 load, but that you get a better margin by using milspec or CCI 450 primers for that application. Jimro __________________ Machine guns are awesome until you have to carry one.