.055"/.062".

"Slightly" off center of a large rifle primer is about .010" to my mind.

It is likely that millions of military rifles were built with "slightly" off center firing pins to the center of the rifle primer and further that these rifles functioned as designed and were within the design tolerance.

As such, if a rifle firing pin is "slightly" off center and the cartridge is not firing, then other issues are at fault.

It should be noted that double rifle's center point of firing pin to the cartridge primer center will change (move upward) the more the DR is used because the barrel flats get nearer the actions flats as the hinge pin and the forward lump hinge pin hole wear. However, these DR's continue to fire with this slightly off center change.