Ok So I have a 71/88 Beaumont rifle in good shape. I have already made cases to fit from 50/90 star line brass, so that part I have a handle on. Now, help me not blow my self up. I'm thinking that the 43 beaumont has more capacity then the 45/70 right? The reason I ask is, I want to use Trail Boss for a powder. I went on the IMR powder site and it appears that they have a load listed for the 45/70 and a 400 grain bullet. I will be using a 350 grain bullet for my 43B loads. The max load listed for the 400gr 45/70 loads is 16grain. Now, if I load 16gr or under, of Trail Boss in the Beaumont cases with a 350 grain bullet, is that reasonable? Even at 16gr? The data is for trapdoors.