Start with a new barrel. Action and feed rails can be adjusted for the new cartridge while the barrel is off. I have performed this several times in the past. No customer had any complaints.
I can't think of anything right now. I'm well stocked on powder primers and bullets etc. If I think of anything I will PM you back. I also have ADG 300 WM brass that I going to post up as well.
220 Swift new WW primed brass 300 rounds.
220 Swift once fired WW sized and primed brass 33 rounds
220 Swift once fired WW and R-P brass 100 rounds.
220 Swift factory rounds 8 R-P and 19 WW 27 rounds total
$350 shipped.
I have some once fired that came from a ballistics lab in Crawfordville FL. I have used these in my 264 with problems. They are WW brand. What quantity do you need?