Something I often forget about, and most people overlook.....
The sights on Mosins are not graduated in Meters or Yards. The graduations are in
Arshins, which measures out to roughly 28 inches. For 0-100 yard shooting, it works fairly well, to just use the corresponding mark. For 100+ yards, it can cause you to shoot low, though. Adjust the sights a bit, and see what that does for you.
And, just some advice from some one that has reloaded for two Mosins, and several other milsurps traditionally loaded with heavy bullets:
Give Round Nose (or blunt spitzer) bullets from Hornady (.312), Sierra (.311), Speer (.311), or Woodleigh (.312) a try, in the 170-180 grain weight class. It can really help with feeding issues, and often tightens groups up a bit.
My personal favorites are Hornady 174 gr RNs, and Woodleigh 215 gr RNs.