ORIGINAL: eldeguello
My "standard" .45/70 load these days is the old Elmer Keith load of a 400-405 grain bullet with 53 grains of IMR 3031. It gives around 1800 FPS, and is alot easier on the shooter.
Sounds like your 350-grain load is a good one also.
Even that one can be a harsh load. I have been shooting 300gr partitions with 46gr of IMR4198. Its kicking out at 2000fps. But I wanted a good whitetail load. But I am almost out of 4198, and am going to try 3031 next.