Sr 4759 is pretty versatile, I'm going to try it with some heavy bullets once I get settled in a little bit more , I know that they don't make it anymore but I run into it from time to time if you find any, a few months back when I was shooting the 400 grain Fury bullets,I started with 36 gr imr 4198 worked my way up to 46 grains and stopped there now that was with a full shank number 17 barrel also on a begara Remington clone action, I did not get a really nice group until around 44 and 45 grains the light loads did shoot okay inch and a quarter but if I remember correctly 46 grains shot very well. I think sr4759 if you can find any would be very interesting again I'm going to find out. Michigan muzzy if I were you I would consider building a second rifle or getting a second barrel with a heavier barrel shank and do your load work up with that rifle- barrel and then drop your charge a little bit for the break action, I'm interested in heavy bullets and smokeless also but I want to continue to approach it very cautiously. It seems to me if you're shooting heavy lead you're not going to have to shoot as hot a load as I am with the jacketed bullets I'm shooting to get your bullet to swell properly,,, interesting stuff I think!!