At some point in the past, I started to refinish my Mosin Nagant M91/30. You know, strip the stock, do a hand-rubbed oil finish, reblue. The works.

After I reblued the metal, but before I started doing the oil finish on the stock, I had to stop working on it because I became very busy.

So I coated it with cosmo and put it in its case.

Flash-forward a couple months. The stock's been sitting in my garage for a while, and things have become less hectic, so I started on the stock. First of fifteen layers applied tonight.

I take out the gun to look at it. Minor surface rust. Started polishing it off with some Flitz. Out of curiosity, I look through the barrel.

NOOOO! Rust! So I immediately start cleaning it out. CLP, Gun Scrubber, Sweet's, and the surface rust is gone. But there is the enemy of all guns in there still: No, not John Kerry. PITTING!

Deep, heavy pitting too. No way am I using it again. So, I figure I'll get another one, polish the bolt-handle to parade-shinyness, and put the hand-rubbed stock on it, and then put the other stock on Mr. Rusty, solder a metal dowel in the barrel to prevent use, and have a wallhanger.

I still feel bad, though, especially since I paid about twice what the rifle was worth (I was stupid as to values then) to get it, and it didn't have a bayo, cleaning kit, or anything except matching numbers and an [SA] stamp. Not even the Finnish free-floating.

From a recent look, I believe I have allowed a Mauser to do the same thing, and I'm feelin' pretty damned bad myself.

Education isn't cheap.  Just be glad it wasn't a family heirloom.

I hate to rain on your guilt parade but  you'll be surprised how well that thing'll fire with some pitting in the barrel.
My dad's got two 8mm surplus guns; one with a pristine barrel and another that someone apparently filled with mud and salt and left capped for 20 years. I almost think you might see light shining in the pits from the outside.

You guessed it, the pitted one is about 1/3 more accurate. So shoot away, it's not a bench rifle anyway.....