Gene,
Ammunition from different eras or even different lot numbers, will produce different pressure. It is the constant bugaboo with ammunition loaded to SAAMI specs, and the manufacturers hide behind the MAX pressure SAAMI allows, telling folks it is safely under that, but, not by how much. They do this because it gives them freedom to use different powders and components without having to be concerned about anything but the MAX allowed. We have seen promo loads tested and reported on, right here, that were hitting 11,000 psi, not something most of us are interested in using. Dude with an autoloader he has never cleaned, yea, whatever.
They don’t care about you and your Damascus gun.
Best,
Ted
