Basically, trying to guess chamber pressure by taking a look at the primers is like wanting to guess how deep a lake is by sticking your toe while in the h2o. All powders exhibit various "behaviors" .... even in the exact same cartridge when bullet weights differ. As a result, https://jasperjbuzm.amoblog.com/the-2-minute-rule-for-federal-primers-gm210m-53801683