Thread: CIP vs SAAMI

Greetings,
I may have stumbled over the big difference with the .223. Much of the sporting .223 ammo in the US is shot in semi auto rifles where port pressure is important. On the continent this is not the case so the ammo may be loaded hotter. Military ammo works to a different pressure system and the chambers are slightly different. Just my thoughts and I have not dug into it.
GPM.