Primer Piercing and Primer Blanking

What is a pierced primer? What is a blanked primer? Please educate me!

a blanked primer is when you get a small circle around the outside edge firing pin detent in the primer...looks like a small circle etched in the primer around where the pin hit it...usually from the firing pin hole being to big or woren...a pierced primer is where the firing pin puts a hole through the primer cup instead of just the detent.

Thanks, LongRange.

According to SAAMI



PRIMER, PIERCED
A fired primer which has been perforated by the firing-pin.

PRIMER, BLANKED
A fired primer cup in which the firing-pin indent has been punched out by internal gas pressure.


PRIMER CRATERING
A circumferential rearward flow of metal surrounding the indentation of a firing-pin in a fired primer cup.

You can find it all here http://www.saami.org/glossary/display.cfm?letter=P

Thanks for the detail and the link, earl39.
Randy