I was going through my old emails looking for advice from Paco back in 2001 about my stockless .358Win Model 99 Savage. Alot has happened since - illness, marriage, babies, new house, new rifles etc. I bought new wood from the US of A and it is still in its original wrappers

So today i look for advice again.
I dug out my .40-82 1886 Winchester 1/2 magazine rifle. Overall the monster is in great condition except for the front sight blade that moves in its slot ( i was simply going to glue it down ). The rear sight is missing and there is a peep at the rear.
As far as i know its a blackpowder barrel - I can see nothing to indicate a 1890's nickel steel barrel like what is on my .30-40 1895 Winchester musket.
Now I am sure I read back on the old sixgunner.com website that people still loaded modern powders into the .40-82 at old BP velocities without issues. It was the "elephant stopper" loads with modern powders that people made up - that blew the rifles up.
Frankly I dislike blackpowder for obvious safety reasons but do I have any alternatives for such a calibre ?
Once we had great resources online but alas the internet is 90% garbage with 8% almost useful information and 2% gold.
Is there anyone here that loads .40-82 that can assist me some loads to try ?
BTW - What is it that these cresent butt plates ?
Is there a comfortable way of shooting the rifle ? When I shoulder the rifle I can't find a comfortable shooting postion on my shoulder.