I'm really kind of tired of my synthetic .223 and .357 not shooting well. I've been messing around with this for three months and after reaming a lot of material out of the forearm and using several shims, it will shoot fairly good.
In an attempt to find a solution to the continuing problem of poor groups, I took the .223 barrel and put in on a H&R12 gauge shotgun frame and forearm, serial # AU 591xxx. The trigger pull is rather stout, but even so, I shoot a 1 3/4" group of 8 shots at 100 yards. The loads were mystery loads that were given to me, of 24.5 gr of some kind of ball powder.
http://forums.handloads.com/uploads/Paul5388/BBB9B_scan0026.jpg Using the same mystery loads, I changed to the synthetic stock and forearm and shot two 5 shot groups that were 1 1/2" and 2 1/2".
http://forums.handloads.com/uploads/Paul5388/D3Z2C_scan0027.jpg All of this was kind of encouraging, so I went home and loaded a few rounds of surplus IMR 4895. Using the synthetic stock and the shotgun forearm I shot a 3 shot group of 3/4".
http://forums.handloads.com/uploads/Paul5388/AZ81F_scan0025.jpg Obviously, the synthetic forearm is a problem.
Obviously, a properly head spaced .223 barrel on a shotgun frame isn't a problem (even if the trigger isn't target quality).
The shotgun forearm will pass a folded brown paper bag between the barrel and forearm, the total length. When I put the same forearm on my .357 barrel, the right side is closer than the left side, indicating a barrel stud problem (probably welded off center or tilted).
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