Originally Posted by oldNewbie
How critical is primer seating depth in a semi-auto?
I have reloaded a few thousand rounds of .45 ACP. I have never cleaned primer pockets.
That doesn't mean it is unnecessary, just that I have been lucky enough to have never encountered the problem.
I use CCI primers. Do other brands create more residue? I don't know.
Primers must be seated flush or slightly below so they don't interfere with the action going into battery, or cause an out-of-battery firing.
I generally check for this when I run every round through a chamber gauge, by just passing my finger over the primer.
Calipers would provide a more accurate check, but I've learned to check for flush "by feel". I'm not sure the added accuracy of a caliper check is necessary for this step.