45-70 Govt
Just curious as to why your choice for that 500-gr bullet?
Are you trying to get more range out of it, or are you going to hunt with it?
I'm just curious since I used to load a lot of 500-gr loads for the Handi Rifle and Buffalo Classic rifles and other single shot 45-70 rifles such as the Sharps and Rolling Block actions.
If for range, I got a 550-gr bullet you might be interested in that will work real well in your Handi Rifle with its 1 in 22 rifling.