I have 600 large magnum rifle primers and I was wondering if I can use these in some of my normal rifles, ie. .22-250, .308, .30-06. I bought them for use in my .300 RUM but I no longer have it. Can I just back down the powder to minimum levels and go up from there? Also have 100 large magnum pistol primers and I have no idea why I have them. Maby For my .44 mag that I no longer have. Can I use these in anything like my .45acp or a .357 or .500 S&W.