If you just want to break it in drop it to 39.5gr. You're going to get higher pressure and slower velocity on a new barrel. Once you get 50 to 80rds on it you can ladder it. I would also save the 4350 and just buy a lb of something cheap to break in with
Thank you for the advice. I have enough 4350 to get me through the barrel, and I can’t seem to find much of any other powders around unless I could use up some 4831sc in it.