Regarding ammo, the rifle will shoot any .22 L/R you want to. It can also shoot longs, shorts, CB's, subsonic, etc. Some recommend only long rifle ammo. The chamber is very long for the shorter cartridges and may lose accuracy. I should emphasize "may", because I have seen several old heavy military type .22 L/R's that would shoot lights out with nearly anything. In general though, the hyper velocity ammo doesn't seem to shoot as well as the standard velocity stuff. Try every kind of ammo you can find. Something will shoot great. Probably several kinds.
Some of the things I like about the old military style .22 rifles is that they have quality, cut-rifled barrels. I also like the size, weight, dependability, and no frills appearance. I have had several over the years that were over 60 years old. Not one ever needed any kind of repair even though many thousands of rounds had been fired in them.
Tom