Pressure question

  • I’ve seen this several times before but do not know the reasoning. I’m working on load development for a friends 223 bolt gun. Just started an OCW test and the second charge weight had primer flattening on all three cases from that charge weight. The three charge weights above didn’t show any pressure signs at all. I always push past the first signs of pressure for this reason, but was curious if anyone here knows why you’ll sometimes have pressure signs at lower charge weights in a test.

  • Pressure curve.

    There is a timing to all of this. The primer can be pushed out the primer pocket, then shoved back into the pocket, depending on how brass moves in relation to the bolt face.

  • Thanks fella. I’ve always wondered why some did that.