Last spring, I put on a CMP GSM Clinic/Match. On hand was Garands, Carbines, Mausers, Springfields and Enfields.
The guy who won the match shot a Mosin he picked up the night before with some surplus (spelled crap) ammo.
They'll shoot if one takes the time to learn to work them.
I'm talking "unmodified" rifles which are required by CMP Rules in their matches.
CPT USAR Ret
USAMU Sniper School Oct '78
Distinguished Rifle Badge 1071