I might have some 24 ga. plastic shot shells I could give ya that will get ya shooting faster and cheaper. I once planned to get a snider but never did.
Not sure. The "n" in russian cyrillic is actually the letter P. Many times you'll see the n in a circle which means the barrel was proofed. Not sure what your mark means. I'm not an expert either, just spent some time this morning looking it up.
Ok, more research says the the ( ПП ) is an...
I cleaned up a "unmarked", "untouched" Martini Henry MKII and "untouched" MKIV. Great shooting guns, I'd love to get one of those sniders, but it isn't in the budget right now. I envy this project of yours.
Are there any proofs on the barrel, or just the breech? They used some british breech blocks with Nepal made barrels. A really good one also has a british barrel, with "Steel" stamped on it. Sometimes the "Steel" is stamped on the bottom side.
Here is a video a buddy of mine made on the...
The conditions you describe are typical of many of the refurbs. I have two in that shape, both refurbs. There are stamps on the stock and receiver which might indicate that. I also thought mine were new unfired, but identification of the stamps on the stock and receiver indicated...