45-120

[jconley]

All this fuss and you haven't even shot it yet?

I’ve had it for many years, I’ve shot it countless times.

[Lead pot]

The .45-120/3-1/4" with a free bore chamber can be a head scratcher, I been down that path but it can shoot very well. semtav gave some good advice with the bullets patched to groove or snug to the free bore diameter, this is what I had to find to get it shooting well. Also controlling the recoil and torque will be a must thing to master.
Also match the bullet length to the twist of the rifling like Don said. But again the ogive profile even with a proper length can and will be an issue with conditions.
Enjoy the ride and keep notes. The memory chips between the ears seem to get overloaded with time.