M1 Carbine barrel overtightened -site picture aims 3" right @ 50yds
M1 Carbine barrel factory overtightened 8-10 degrees, front site picture also rotated 8-10 degrees counter-clockwise causing my point of aim right 2-3 inches at 50 yards, Tight groups 2-3" max. Will center on target with rear sight windage adjusted completely to left. Can this be fixed by untightening the barrel and rotating it clockwise to center my site picture? Will this effect my accuracy, reliability, or safety. Is it an easy fix that can be done at any good gunsmith, or should it be sent to Fulton Armory for repair? My rifle is a beautiful, clean, reliable aftermarket carbine made by IAI - American Ledgend series serial #M888/2015XX. It has new original USGI parts. An IAI mfg barrel, bolt, and receiver. Assembled at the Liberty Armory in Texas. I would like to fix and keep for home defense and target shooting, but will consider selling if too many $$$ to fix or if accuracy, reliability, safety affected by repair. May replace with the new 580series mini-14 in .223. any thoughts/insights on any of this is greatly appreciated. Thanks, Mike
reference at: Israel Arms International
The other thing is when you unscrew the barrel
you lengthen headspace. Probably not enough to have much effect, but you should be aware. The bolt stops on the receiver lugs, the barrel will move away from the bolt when it is unscrewed. The chamber is cut when the barrel is installed. I had a similar problem on a 5.4 Garand and they backed it off a hair at the CMP, it just barely passes a field gauge (1/16" of closing but still passes). The carbine usually relies on the extractor to position the cartridge case but it really should (is designed to) chamber against the front edge of the case. A .45 works similarly and almost always is controlled by the extractor. I don't think that the carbine is as sensitive as say a 30-06 to excessive headspace because it is a popgun compared to that big 30-06, but it isn't a .22 either. Most of the government test carbines noted in war baby either had excessive headspace at the beginning or end of the test. They still worked fine and probably were not life threatening.