I know this is an old thread, but I got a Tom Horn 1876 in 45-60 a few weeks ago. Really like it! This is my best load so far, photos from getting it sighted in at 30 yards.

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Bullet: GT Bullets 325gr FN (.459/GT Lube/Hornady GC/96-2-2)
Powder: AA 5744 24.0 grs.
Primer: Federal 210
Case: Starline Converted 45-70 Government
LOAL: 2.230
Avg. Vel.: 1255 fps
ES: 19
SD: 7

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