Tom Horn's rifle
Just a technical point for you all. The Winchester rifle that Tom used was a Model 1876 Centennial Model in 45-60 caliber. This was a relatively rare gun made by Winchester. It fired a 45 caliber (45/100th inch diameter) with 60 grains of (originally) black powder. This gave it less power and recoil than the Springfield 45-70 Govt. cartridge that many buffalo hunters used.
In this film, Tom says that this rifle had a trajectory like a rainbow, but a 200 yard shot (like the one that killed the kid) is not that difficult with this rifle. Tom's comment about how it would be his "greatest shot" just isn't true.
In the Ted Turner production of Louis L'Amour's Crossfire Trail (2001), Tom Selleck's character, Rafe Covington, buys the same model and caliber rifle in the town where his friend, Charles Rodney, had lived. In fact, his friend had ordered the rifle, but died before it was delivered.