I had this very discussion earlier today. The primer cup on rifle is thicker than pistol. Different manufacturers have different thicknesses such as CCI is the ones the military use here in Canada(I think) and they are thicker than the rest so harder to fire. No accidental discharges hopefully. Federal make thiner softer pistol primers so you use them in revolvers with light triggers so they go off. Rifle primers have more snap, magnum have more than that and match are very consistent. Not that I can tell the difference. If you use pistol primers in rifle, you stand the chance of getting no or partial detonation of the powder. Also hangfires happen. Click-boom. If you use a rifle primer in pistol you may have the primer standing prowd, that is not fully seated. Do this in a .45 you may get an out of battery detonation. Is that what you were asking?