It is last because it is too big and heavy for me. But I wanted to build the closest copy I could. It is correct in all dimensions to Jim's rifle. The barrel is from Oregon Barrel Company, 33 1/8" long, 1 1/8" straight, 7 lands with a 1 in 48" twist. I filed the muzzle like the original and can thumb start a patched ball half way into the muzzle. The bottom rifle is my first copy with a shorter GRRW barrel. It has been shot probably a couple thousand rounds by now.
I shot it from bench at 50 yards starting on the bottom target with 50 grains (weight corrected measures) of Goex 3F, .530 Hornadys, and .018/.010 (crushed) pink linen, which was too tight, though all fired patches were good. Velocity averaged 1311 with 72 fps spread. I guess I was learning how to shoot this rifle, it will group this load well, will try it again.
Top left was next, 100 grains of Olde Eynsford 2F and .018/.008 patches, of which three blew out. Velocity for four was 1888 fps, 39 spread.
Top right, 100 grains of O.E. 1 1/2F and .016/.009 linen, all fired patches good. Velocity was 1852/23 fps and the group was 1.25 inches. I had a damp cleaning patch on the seater jag, otherwise no wiping.
I need to file the front sight .040 inch to raise the group three inches for a 100 yard zero. The rear sight is Track's "Jim Bridger's rear sight", #RS-KC-18, which is .290 above the barrel at the notch. Jim's is .335 and my handmade first Bridger sight is .315 high.
There was discussion here in the past about a 48" twist being too fast for heavy load accuracy. I found these two loads gave higher velocity than the 1-60 twist GRRW barrel of my first Bridger. That barrel is 2" shorter, but that would not make much difference. With it, 7 groups of 30 shots of 100 grains w/m of Olde Eynsford 2F averaged 1782 fps with 41 fps spread. The 48" twist gave 1888/39 fps, 106 fps more.
In the GRRW 1-60, ten groups of 53 shots of 100 grains of O.E. 1 1/2F averaged 1760/60 fps. The 48" twist gave 1852/23 fps, 92 fps more.