It would not surprise me, that company's might possibly interchange some of the primers. For instance,sm.pistol mag. and small rifle std.
Beer company's back in the '60's and '70's, here in Ohio, had to make what was called 3.2 beer. Lower alcohol for Sunday sales, and at that time, 18 to 21 year old drinkers. The main difference was a red cap on the bottle, or printed on the can. My family was in the carryout business, and went on vacation one year,to St.Louis, to a major beer brewry, which will remain unnamed. While touring the plant, we seen the capping part of bottling. We seen the worker putting in red caps, on top of blue ones. My dad asked how are they going to tell the difference in the beer, since the line was running about 10,000 bottles an hour. (maybe more) The worker just laughed and said, that the 3.2 beer labels, were going to the state's that were stupid enough to think they actually made a different beer for 3.2.
So is there a difference in primers. maybe. Until I get to see them coming off the line, I'll play the game and assume there is. gypsyman