I went and bought 100 Acme .458 405 gr bullets. They are coated red. I am using them in a 45-70 Gov. and wonder how fast I can push these bullets. They are 16 hardness. I am not using it with black powder however, I am using 14 gr of Unique powder @ about 1150 fps. I know it's a mild load and want to use it for deer. I never had a chance this year however. I dont need to push it all than hard but was wondering what the speed limit is on these bullets if anyone had an idea. Thanks in advance .

I just ordered some for mine...dont want to push them more than 1500 fps or so as its not needed for deer. Acme says you can push these faster than traditional non coated cast bullets but how much faster I dunno. Id contact them directly.

There's no hard and fast rule. You can simply work up a load ladder, and when accuracy turns to crap, and your groups open up WIDE, you've exceeded the bullet's abilities. That's what I've done with many different alloys in dozens of bullet styles in over a dozen guns. Most guns will shoot most alloys faster than most people think they should. Coated BN 16 alloy should be good for anything you can do in a 45-70, unless you are trying for 458 Win lite.

i had a Mauser 45/70 that i ran some through around 2200. got best accuracy around 1850

I will try it to 1850 fps if I can handle the kick. Its an Encore with a very light barrel. Kicls like a mule but I like it cause it's light. I run 14 gr. Unique for late season deer hunting. I can't see a thing past 40 yds anyway and want the bullet for my bear loads this fall.