I am tninking of casting bullets for my buff. classic 45/70. It shoots re. .457 jacked 405 gr. bullets very well. Does anyone have any info as to a good mold to purchase that would give me the same bullet diameter? Powder choices and weights would also be appreciated. thanks m_s

The first thing you'll need to do, is clean out all the copper jacketing from the barrel.
Your cast bullets will need to be 1 to 2 thousandths larger then the barrel. My guess that will mean .458 to .460.
The first mold I had for my 45-70 was a Lyman 405 plain base. I found it to be accurate and easy to work with. I didn't pursue that mold as far as I should have because I found a Lyman 445 grain gas checked mold that worked even better.
Recently I've been working with a 350 grain Saeco mold in my 1886 Winchester. The cressent butt plate on that Winchester inspired some nightmares while thinking about the 445 grain slug at a healthy velocity.
For the 405 and the 445 slugs I found IMR4064 worked best for me, considering accuracy, velocity and percieved recoil. Basically the case was full and when seating the bullet the powder was compressed.
With the 350 grain slug I've found that 50 grains of RL-7 gave me a nice pleasant load.
Jim

Jim:

you say: For the 405 and the 445 slugs I found IMR4064 worked best for me, considering accuracy, velocity and percieved recoil. Basically the case was full and when seating the bullet the powder was compressed.

With the 350 grain slug I've found that 50 grains of RL-7 gave me a nice pleasant load.

F: What estimated velocity do these combinations give you? And the same for accuracy: How well do they shoot @100 yards?

Good morning,
Forrest

Missed_shot, I have a Marlin Model 336 (microgroove rifling) .45-70 that shoots the Lee 405gr. HB bullet very well. Although a bit lighter, Lyman #457124 is equally accurate. Btw, I size mine to .459" and use Accurate Arms' XMP 5744 (27gr.) as my target load. The same amount of H/IMR 4198 is also good. Black powder (70gr. FFg or FFFg if a "slow" brand) is higher maintenance, but also accurate with the above mentioned CB's. You'll have to use a BP lube though. Hope this helps, ...Maven