Update: Today I sighted in and shot for accuracy at 100 yds, an Izmash Biahtlon with Weaver K-10 scope, a Browning T-Bolt with Weaver K4 scope, and a Marlin 81DL with Weaver B4 scope. The Marlin was given to me by my father in 1946. I added the scope some years later. It's fired at least 10,000 rounds, msotly high velocity, and the headspace is a little loose. Surprising how well it shoots. It was only 90+ degrees and there was a brisk wind at 5-7 O'Clock, which has an effect on slow 22 target rounds at 100 yds.