Well, I believe it was a bullet diameter issue, compounded by a rough bore.
The 1/20 twist should provide good stability even below 1000 fps with 500+ gr bullets.
The bore was rasping off lead like crazy, and same with copper. So, I fire-lapped the barrel. It shoots pretty good with jacketed 405's at 1500 fps (2 moa via XS ghost ring sights), and I have loaded up some soft low velocity (about 1200 fps) cast bullet loads to try out. I'm curious if the leading issue is reduced by the firelapping. I think it will be, but the proof will be in the pudding.
