Underhammer maiden voyage

I finished up my Underhammer build last week so I hit the range for a test fire.  The barrel used is a GM LRH 50 cal 1-28 twist. Load consisted of 75 grn Swiss ffg, 1 54 cal wool wad and a 420 grn accurate molds 50-415 I, lubed with nasa lube.  Only 50 yards, just seeing if it would go BOOM.

SWEET!! I hope to get to shoot it someday soon