Ramshot True Blue is a great powder to use for .357mag. It's a ball powder that meters very nicely and in my experience have shot well with 158gr lead bullets and 125gr jacketed bullets. I've only ever used Remington and CCI small pistol primers (non-magnum) and they work fine based on shooting ~3,500 rounds through my Marlin.EDP wrote:[...]Lastly, the.357mag rounds I am going to start on next - I want to use the PPU copper-jacketed bullets in the PPU cases (as I find their factory rounds are great in my lever action) so I won't have any leading issues anyway with that calibre, but I'd be very interested in your suggestions re: powders and primers to get as accurate as I can with them?
http://www.ramshot.com/wp-content/uploa ... _Web-1.pdf
For gallery loads I've used Alliant Bullseye with 158gr lead bullets in order to keep my velocity down.
The key with loading these rounds for a lever action is making sure the overall length isn't too long. If my memory serves correctly, my Marlin doesn't like to be fed anything longer than 1.600" so I load mine to around 1.590" and they feed really well. In my experience I haven't had any problems with leading; I've only ever cleaned my bore when I've shot jacketed rounds.