by LawrenceA » 30 May 2021, 8:46 pm
Just make sure your pills are fatter than the bore.
Hoestly you are trying to get the cast pills 2 thou over the throat.
The SAAMI specs forthe 45-70 is no throat so you need the bore diameter just ahead of the case mouth.
Going 2 thou over will prevent gas cutting and leading (assuming everything else is right).
This is particularly important with micro groove barrels.
Best to get this by using pure lead to cast a half bullet in whatever mold you have and flatten it a little. Measure it to make sure it is at least say 461.
Then tap it in from the breach end to about n inch in front of the chamber and then tap it back out.
Otherwise talk to the local blackpowder club and get a couple of 50 cal balls.
Then do the same.
If you want I can send a few bullets your way in 45 or 50. Think I have a few hundred somewhere.
If you really want to know what is happening do the same at the crown end and lastly push one right through.
Hopefully it is slightly larger at the bore with no loose spots and maybe a slight constriction at the crown end.
One well placed shot is all it takes.