Re: Smokeless load for a 45-120
If that's your goal, there's a way to do it. I'd suggest looking at Hodgdon's site and checking out the loads they have for 45-120 Sharps.
Keep the pressures below 35ksi, even if you think it's OK to go hotter. I know the temptation to shoot harder, but just keep in mind that thing is more than likely built right around the time the Bessemer process was really starting to be refined...
My dad just got a Martini-Henry in 45-577, it's a really cool rifle, and some people think you can load it with smokeless, but his mindset (and I agree completely) was this:
"It was designed for BP pressure before people even invented smokeless. It killed people at hundreds of yards, and I have other stuff that will reach further. If I want to shoot that far, with something flat and fast, get the right tool from the shed. Don't try to plow the field with a garden trowel"
BTW, can you snap a pic of your rifle? I'd just like to see it, those old bastards are really cool. I dunno why, but maybe that's why I keep a CR license