Get yourself the book "The Mosin-Nagant Rifle" by Terence W. Lapin. It will tell you eveything you need to know about them. I collect them; have 14 of them. I have a 91/30 that I am making intoa balloon shoot rifle. It likes cast bullets. I installed a Pacific cocking piece sight on it. If you want one of those sights you will have to find a dealer in old receiver sights. Pacific went out of business long ago. The Mosin is an interesting rifle and was made in different variants. Mod. 91's are kinda hard to find as opposed to 91/30's. They can be fairly accurate rifles. They are in the same power class as the .308/30-06 cartridges.
You can find sniper ammo but it is salty. I bought a package of 20 for $20. Be aware that surplus ammo is generally corrosive. However the newer Wolf is non-corrosive. Better yet, reload for it. It is easy to reload and any .308 bullet will work. Sierra has a bullet for the .303 that will work for the Mosin.
The Finnish rifles are the best. Most common is the Mod. 39. Very nice rifles.
BTW, the front sights come in different heights. You just have to measure them.My one 91/30 shot high so I put a higher front sight on it that I took off one of my other 91/30's.
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