About time this forum loads! Kept canceling out on me all darn day.
Anyway, its a .50cal with 1:48 twist after doing the ramrod trick to figure it out.
No clue who made it, the barrel and stock are all custom, no markings on the barrel.
28" barrel with the 1:48 twist and Deep groove rifling. Looks like an L&R lock on it.
I got it down on my tack driver bag rest at 50 yards with 90gr American Pioneer 3f and the 250gr .500" Thor. Tomorrow i will try round balls.
250gr Ballistic Tip Thor. Group measured dead on at 1" center to center.