PRIMERS AND PRESSURE
Sunday, March 06, 2011 (19:53:46)

Posted by Vince

PRIMERS AND PRESSURE

by James Calhoon
(First Printed in Varmint Hunter Magazine, October, 1995)

In the course of talking to many shooters, it has become clear to me that the manufacturers of primers have done a less than adequate job of educating reloaders on the application of their primers. Everybody seems to realize that some primers are "hotter" than others and some seem to shoot better for them than others, but few reloaders know that primers have different pressure tolerances.

I ran into this problem myself when loading a 223 to the maximum. The primer I was using was piercing before the case began expanding at the head or reaching maximum pressure. How do you check maximum pressure without a laboratory pressure gun, you ask? To check maximum pressure on a given powder / bullet combination, measure the rim of the cartridge (at a specific point each time of the measurement) before and after firing. Cases don