Brad

I reread your original post and was curious if you ever found out who rebarelled it? It is possible that you have regulation problem with the new barrels and may just need to go and get it done.

Also, have you cast the chambers or run the fired cases through your sizing die yet?

Bad

I use 140 and 143 grains IMR 4831. 140 and Woodleigh Solids gives me 2" at 50 yards. 143 and Woodleigh softs shoot to the same point of impact giving me a 4 shot 2+ inch group at 50 yards.

I've always wondered if the depth the wad was set with R-15 made any difference in accuracy. Any opinions?

I would also be sure what ever wad I was using was compressed between the bullet and the powder. Also I would use a heavy crimp, which I find best to do in two seperate steps, IE seat all the bullets first then go back and crimp them.

From the A Square Manual 26" barrel

H-4831 153 gr. 1925fps

157 gr. 2034fps

163 gr. 2128fps 34,600 psi



IMR7828 165 gr. 1967fps

167 gr. 2071fps 34,100 psi



RL-15 132 gr. 1980fps

135 gr. 2081fps 30,100 psi



Hope this helps. Keep us posted on your results. I think there is a 577 or a 600 in my future.



Post edited to change IMR 4831 to H 4831.