Welcome bradVA, your going to have a great time with that 45-70. In my 45-70 I use imr 3031 and have good results with all my loads. If you stay with the loads for the trapdoor springfield, recoil shouldn't be too much of a problem. As you get up into the lever action loadings it can become quite stout,and the Ruger #1 loadings can bring tears to your eyes.Also remember that the heavier bullet weights kick a lot harder,so staying with the 300 -350 grn bullets will help also. If this is your first handy I must warn you, ther will be more of them in your future. It 's an addiction that just buying the extra barrels won't completely satisfy. we all seem to have 3 or more complete rifles ,AND,a few barrels too.