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View Full Version : looks like my M1 needs some work - opinions please!



Bayou
05-10-2009, 11:42 AM
Range report 5/4/09

Bought my first M1G about six weeks ago and got her to the range this past Monday. I disassembled, inspected, cleaned, lubed and replaced the op rod spring, hammer spring and clip ejector spring (which was broken). On the bolt face I could see a circular imprint centered on the firing pin hole that was the size of the primer but I couldn't feel much erosion on the surface. That was the only issue that concerned me from the inspection, and the fact that the rifle was inspected by me, a Garand rookie.

I shot two recipes of my own reloads. I started out with a traditional M1 powder 47.0 gr of IMR4895 behind a 168 gr Nosler HPBT match bullet and the stock gas plug. For this load the chrony results for 8 rnds were:

ave velocity 2475 fps
spread 46 fps
std dev 15.5 fps

I was using open sights at 50 yds, observations follow:

1) grouping was disappointing being about 2 inches for a 4 shot string
2) The primers backed out about 0.010 inches
3) The clip ejected after 5 rounds with three rounds still loaded
4) The ejected rounds seemed to be scattered over a wide area and some I believe even bounced off the canopy covering the shooting tables which is at least 6 feet above the rifle.

Second recipe used 55.0 gr of IMR4350 and an adjustable gas plug. After shooting about a half dozen rounds to dial in the Schuster plug the chrony results were:

ave velocity 2561 fps
spread 49 fps
std dev 15.0 fps

All of the above observations also apply to the 4350 load, except the clip came out after 6 rounds.

Since this was my first time shooting the Garand I don't want to place too much importance on the group size. So I'm not ready to write the barrel off just yet. However the average velocity for the 4895 load does seem a bit low based on other posts I have read, I guess that could point to a barrel erosion issue.

I assume the backing out of the primers is due to the bolt face not being perfectly smooth and the primer sized imprint I could see on the bolt face was a tell tale sign there might be a problem. Can bolt faces be machined back to smoothness or do I need to get a new bolt?

What about the clip ejecting early and the scattering of the ejected cases?

I would appreciate any opinions experienced shooters of the M1G may have about the observations above and the best way to go from here.

Thanks, Bayou

Litt'le Lee
05-10-2009, 01:43 PM
you didn't mention your barrel cindition or the gas cyl and op rod condition

musketjon
05-10-2009, 02:47 PM
Sounds like you may need a new clip latch spring. Take your old one and stretch it about 1/8 inch and try it again. If the clip fails to come out now (except as expected after the 8th round) the spring needs to be R&R'ed. Also check the clip latch where it engages into the clip itself. The edges should be sharp and not rounded or chamfered. If they are, the CL needs R&R. What kind of clips R U using? Some after-market clips are problematic. Try using genuine USGI clips. That's all the easy fixes I can come up with right now. I'm sure someone else will chime-in here soon. Keep us posted with trials/results and we'll get you up and running in short order.
Jon

goo
05-10-2009, 02:54 PM
2" @ 50 yards is probably within spec. (4.0 moa)

Bayou
05-10-2009, 02:54 PM
you didn't mention your barrel cindition or the gas cyl and op rod condition

No measurements for throat or muzzle erosion but visually the barrel looks pretty good. No rusting or pitting and the rifling appears sharp. I didn't know what to look for in the gas cylinder, it appears clean and free of rust. The piston on the end of the op rods looks nice, not a mirror finish but not far from it either.

Griff Murphey
05-10-2009, 06:28 PM
I run 43 gr. H-84895 with 168's and old pulled 173 grs. You might back off your load a bit.
All M-1s have that mark on the bolt face, at least, all I have ever seen.

Chilly
05-10-2009, 07:24 PM
I'm concerned for the primers backing out way more than your non-match grade accuracy. I think you'd better check your headspace. I'll bet it's long out of spec, which will also will cause poor accuracy.

Kirk
05-10-2009, 09:14 PM
Replace your clip latch spring; that is probably causing the premature clip ejection. In the meantime, you can add a "helper" spring by using a spring from either a ball point pen or BIC lighter. They are small enough in diameter to fit inside the CL spring. Trim the helper spring to be about .05" longer than the CL spring.

Bayou
05-10-2009, 09:26 PM
I have a new clip latch spring, came with the spring kit. It seemed like the one that was on there was still functioning well so I didn't install the new one. But I have no idea what it should feel like so that was just a guess. I'll put in the new one but before shooting her again I'll have to do something about the primer issue. Thanks.

Griff Murphey
05-10-2009, 11:47 PM
I would have the headspace checked. It may be that another bolt will correct the problem. M-1's really toss the brass all over - don't worry about that. I belonged to a club with a tin roof over the benches. For high power bullseye matches the shooters stood in front of the benchrest firing line and we had brass up on the tin roof all the time, as well as everywhere else. Not M-1A/M-14s; they pile them up neatly at about 2 o'clock. But M-1s throw them EVERYWHERE.

ltcboy
05-11-2009, 01:30 AM
The op rod piston should mike out at .526. I would also make sure that when ytou shoot, the gas cylinder locking screw is tighten. These will come loose and your accuacy is comprimised. I would also think about getting a throat erosion and muzzle wear guage. These will tell you the wear of the barrel. These tools can be easily bought online. In the meantime, I would stick a USGI bullet into the muzzle, if the muzzle allows the bullet to go down to the brass casing, it's worn.


Mike