While I have not shot those exact bullets you speak of, I shoot only lead in my BC. 405 grain flat point, 405 grain hollow base, 500 grain flat point, etc. I use "trap door" loads out of the reloading books. Even the higher end trap door loads can let you know when you shoot them!
I have used Trailboss and Hodgdon H4895 and H4198. This list don't allow us to give out powder measurements.
he bottle of trail boss or H4895 don't go very far. So I been using H4198 since it also works in my 32 Winchester Special. The H4895 loads kick harder then the H4198. It gets uncomfortable to shoot 50 in a day.
I have "hits" on the steel turkey at 400 meters with lead. There is no mistake when you hit the target, it rings loud and clear!
Now that I got my new glasses I can see the ram at 500 meters, he is my next challenge! (this is with a tang sight)
With the lead bullets I keep the speed down to around 1400-1500fps. With the gas check ones you can move them faster without leading, but I have no experience with Gas checks in 45-70. I figure a lot of buffalo fell to straight lead at long ranges!