I have approx. 1500 older large primers; the container's are marked as follow's: WESTERN NO. 7 Improved, non-mercuric, non corrosive Primers for Smokeless Powder. Western Cartridge Company Division of Olin Industries East Alton, Ill. My question is, are these primers for large pistol or large rifle? Could not find any info on the cardboard containers or elsewhere pertaining to whether pistol or rifle. Also, what's the real differance between pistol and rifle primers? I'm assuming that the charge is differant for each, and a rise in pressure would result,if say for instance, a large standard rifle primer was used in a pistol case.