Generally referred to as “Fire lapping” check out these people for a commercial setup:
http://www.neconos.com/details2.htm
I used their 22 cal kit for a pretty rough S&W Model 22A barrel that substantially improved accuracy.
Midway USA has bullets in various calibers that can be handloaded to polish the bore of a rifle or handgun barrel.
Carburetor cleaner.
I would not worry about any minor imperfections unless the gun is shooting poorly.
With these older mil surps it’s usually a better bet to rework the muzzle crown because the crown is usually worn out or damaged from improper or excessive wear caused by the cleaning rod during cleaning
Midway USA sells the pre-loaded ammunition in several calibers. The .223 just happens to be backordered.
you don’t need ammo to lap a bore, you can do it by hand.
I am completely of a divided opinion as for the need for this (see rdcbn’s post). I ‘think’ I improved a Savage 110’s accuracy doing this, but I’m not certain. If I did, the difference was small and could be attributable to operator error/deviation.
Then, last September, at 168 yards (why the odd distance...max range on that particular lane), with a Model 70 in 30-06, I shot a 7/8” 3-shot group. That rifle has the most unholy looking bore I’ve ever scoped and I’ve owned it from new in ‘94.
Go figure.
When I was building my last Savage 10, I followed the 50 round procedure Savage recommends for their barrels. I was more than happy with the outcome. It was kinda drawn out and took a while and several six packs and bore brushes to accomplish.
By the end of the break in, the barrel remains relatively clean and is very accurate for a suppressed 24”.
Not sure is this is what you are looking for, but the procedure is listed on the Savage website.
ping for further ruminations...
Minor bore imperfections in a Moisin Nagant don’t matter, unless you have one of the sniper models.