Sources of pressure

308sako

Gunny Sergeant
Full Member
Minuteman
  • Feb 15, 2008
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    Brothel Nevada
    Recently working with 2 different .260 rifles. One an AI the other a JP. what I am finding difficult to understand is why the gas gun is apparently so much more sensitive to pressure. This is based on my "ignorant" assumption that regardless of the breech in the chambers and ammunition should be yielding similar pressures.

    So what am I missing here?