View Full Version : M1 Garand extractor/ accuracy issues
November 26, 2005, 11:16 PM
So, a few questions, and one comment for you guys. I bought a "Tanker" Garand a couple of years back, and it has been fun. Of course, accuracy is horrible compared to my bolt action sporters. However, I can bust the gong (18") at 250 yds offhand, which is great fun.
The last time I had it out, it suddenly stopped extracting cases. A tap of the butt on the ground would allow the brass to fall free, so it wasn't a bad load/ case issue. After disassembly, I found nothing unusual with the extractor, nor any other parts. It extracts loaded rounds just fine. Odd...so, while I had it apart, I looked at the muzzle crown, and it was horrible! I re- crowned the muzzle and am anxious to see if it helped. Now, how loose is "normal" play in the barrel? I can take the front sight and rotate the barrel about .100" back and forth. Does someone like Fulton Armory make washers to take up the barrel play?
BTW, my load is W-W case, Rem 9 1/2M primer, 46.0 grains H4895, and a 147 gr. FMJBT.
November 27, 2005, 01:14 PM
Yikes! The barrel should be tightened with way more torque than you can loosen by hand. Spec is something like 80 ft-lbs? Even with a 90° shoulder, the barrel should be hand-tight with about 15° of rotation left before the sight on the gas cylinder is upright.
Are you sure the barrel is loose? Not just the gas cylinder?
Two scenarios for you:
1. The barrel is actually loose. The general cure is to roll the shoulder to set ist edge back. This has to be done on a lathe equiped with a roller for the tool holder. I had to make one of these tools when I needed it, but SA or anyone else who builds these guns will have one.
2. Second, only the gas cylinder is loose. Tighten the gas cylinder lock screw. You can acutally remove the gas cylinder and peen the edges of the splines on the barrel until the cylinder tightens up. This needs to be done correctly to avoid getting the cylinder and sight out of time with the barrel threads.
Either of these situations could cause extraction problems. A loose barrel or a loose cylinder can put the operating rod out of position and cause it to bump the bolt out of position by hopping its rail. The loose barrel can deflect and cause the extractor to bounce loose of its hold on the case rim.
Either way, you need to get this fixed before you shoot the gun any more. You will at least damage the op-rod if you don't, and at worst have a case burst. My first recommendation is to return it to the maker. Even though you ordinarily need an FFL to send a gun somewhere, the law makes an exception in the case of sending a gun to the factory for repair, since they want people to keep their guns safe. If the barrel is loose, the maker is the one who set the shoulder back too far in the first place, so they should fix it on their dime.
Rolling a shoulder to correct excessive setback
November 27, 2005, 01:56 PM
By the way, the looseness will cause inaccuracy. You should be able to get this gun to shoot under two inches at 100 yards without any accuracy work. If you re-crown and tighten the gas cylinder on the spline and get the barrel correctly installed and make sure the sights aren't loose, it should do that with the right load and no further adjustment.
Every 147 grain bullet I've tried in my NM M1-A has been just terrible on accuracy. To see what the gun will actually do, get a box of Sierra or Hornady 168 grain match bullets and, if you are using modern Winchester cases, try starting with 40 grains of 4895 and work up. You are looking for smallest group, not maximum load. Usually smallest groups occur in something just under maximum loads, but it could be less. That just depends on your gun's harmonics. And don't trust this load in other .308 cases. The Winchester .308 cases currently have the greatest powder capacity, so same-load pressure will be higher in other brass.
If you don't like the added recoil from the heavier bullet weight, try going to the Sierra 150 grain MatchKing. It should do reasonably well in this gun, but the load will be a bit warmer. After you know what the gun is capable of, then see if you can find inexpensive bullets that still group from it? At least you'll have a basis for comparison.
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