I'm Ross, new to the TMA, old hand at ML's. My current challenge is a .38 schuetzen rifle. I've always been a round ball shooter but wanted to try something new. R. Grunkemeyer built the rifle and it also comes with a .40 round ball barrel, which I've no trouble making shoot very well. The .375 groove depth slug barrel is a long and different story. You simply can't beat a .375 bullet down the barrel. Production mold makers also don't make .370 bullets. Paper patching was my next try and after several different sizes a .362 brooks mold showed promise but the false muzzle kept tearing the patches. I had to load paper patched bullets directly into the muzzle to prevent tearing and I now get ok groups with this combo of .362 bullet and 2 wraps of .0017 paper.
I finally stumbled onto a .369 sizing die from NOE and ran some bullets from my .379 mold through it. .010 is a lot to size but it works. Next was powder charges, started at 30 grs. ff Goex and went up to 60 grs. %0 grs worked the best giving one hole groups at 50 yds. So now it's out to 220 yds for my next trip to the range and shoot this rifle at the distance it was made for. I have a .370 mold with a .375 upper driving band coming from Steve Brooks, I have high hopes for this. Any further hints will be appreciated. Ross
ps. R. Grunkemeyer does very nice work