Casting handgun bullets.

[PJgunner]

About to start casting for my 45-70. I have been thinkin about grabbing moulds for my 45 colts as well.

GoodOlBoy

I think that I would go with either the RCBS 300 gr. or 400 gr. bullets for the 45-70. (Sorry, I don't remember the mold numbers offhand.)
For the Colt's, a bullet that has worked very well for me is the RCBS #45-255-SWC.
Lyman does make a 300 gr. bullet for the 45-70 (#457191) but I do not recommend it. For your Marlin, you'd need a bullet yhat will size to >459" to maybe .460" to shoot well without leading and the lyman bullet in the several molds of that number have cast bullets exactly .457", great if you're using almost pure lead and black powder. To be perfectly honest that bullet leads bore badly. I've shot it in the .458 Win. mag. at black powder velocities, and in four 45-70 rifles of my own including an early New Model 1895 marlin, two Ruger #3's and a Ruger #1. The only use I have for that mold these days is for use in a Ruger Bisley Super Blackhawk where I size that oversized (for that gun) bullet to .454". Makes for a good heavy bear stopper, although frankly, I think I like the 255 gr. bullet better. Something about that Elmer Keith design that inspires a lot of confidence in me.
One bullet that had worked extremely well in my Marlin is the Lyman #457122, a 330 gr. hollow point mold that has proven to be accurate in the Marlin and the Ruger. It is a bear to cast good bullets though as are all hollow point molds.
Paul B.