primer leak

primer leak

[′prīm·ər ‚lēk]
(engineering)
Defect in a cartridge which allows partial escape of the hot propelling gases in a primer, caused by faulty construction or an excessive charge.
References in periodicals archive ?
By way of contrast, the same bullet ahead of a published load from a 1960s source gave a velocity of 3,650 fps, and the measured pressure was 71,800 psi (with a slight primer leak).