Actually Chuck it can make a dramatic difference. I cannot recall where I read the tests before but it was probably in Hand Loader magazine and in one of the loading manuals. A change of 1500 psi is possible. The Alcan primer was a very hot primer back then. From the Lyman First Edition Shotshell hand book all loads for the Alcan 220 Max-Fire primer are for use with their powders or their wads wich are no longer available. I would try them with 16 GRS of Red Dot and 1oz of shot with the appropriate wad and I would feal confident that they were safe.
