Gave 4831 sc a shot today with the 77tmk, new alpha brass, fed 210. Have a 22 inch PBB 7.5 twist.
This is my wife’s gun so she did the shooting with it today (except for the 45 grain charge below).
First charge was 41 grains and it was slow! Got 2985fps average out of it. Ext spreads were in the 60 fps range. About 2.5 inch group. Worked up to 45grain before I found pressure and that produced 3228fps and 50 fps ext spread. The 45 grain charge grouped about 1.2 for 10 shots.
41 grains of H4350 did the best so far. Got 3247fps with around 25fps of extreme spread. The group was good at an inch. I want to say she pulled the couple shots to the right but she felt good about them. She let the rounds cook in the chamber a little longer than I would have liked but no pressure signs.
The barrel has 70 total rounds on it so far and hasn’t really showed any signs of speeding up from the last load of 41 grains h4350 that I shot.