If you down loaded ,,,say big 'buffalo rifle' rounds with BP, you use fillers, wads,,ect,,,,to take up the space.
Why do you not have to use fillers/wads,etc,,,to take up the air space if you have a smoke-less load that leaves space in the case ?
I have a bud that loads some 'recreational plinkin' loads in his 45-70 with Trail Boss and there is a mile of space in the case.
Why the difference ?
MD