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Old October 27, 2022, 08:58 PM   #1
nhyrum
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M1 garand won't cycle.

I recently got a garand. When I bought it I also bought a bandolier of 6 clips(still getting used to saying clip ) of "m2 ball" that is ppu stamped and definitely doesn't look surplus. I took the gun out and shot 4 of the 6 clips, and the gun ran fine, with maybe 2 instances total where it closed on an empty chamber. I took the gun home, and following the Brownells series of videos, carefully took the rifle apart, cleaned, and lubricated it.

I then proceeded to start working up a load to copy the m72 load with 175 smk's and imr 4895. I started at 43 grains and worked up a set up to 46. None of the ammo cycled, so I figured it was just that it was the low charge weight. I brought my chronograph, but the battery connector broke, so I couldn't use it that day. The federal primers I used should be able to warn me before I get too hot a load, and as I was still low in the book, wasn't terribly concerned with bending the op rod with these. To rule out the possibility of it just being the ammo was not producing the gas the rifle needed, I decided to try a clip of the ball ammo that functioned earlier. Every shot closed on an empty chamber, but it did eject brass about 6 feet to the 4 to 5 o clock position, and the clip does eject.

I broke the rifle down again, this time watching multiple videos, and paying close attention to just about every detail, did a thorough clean and relube. Went back to the range today with my chronograph fixed and a new set of test loads at 46.5 getting of 4895, which from my reading is what most say the m72 is, and the 175 smk is close enough to the 173 grain bullet used. Shot over the Chrono they ran about 2400, which is about 200-250 fps short of what both books and what the m72 load is.

Any idea what the issue could be? I don't believe the op rod is bent, as it worked fine before my disassembly, but not after, with the same ammo. But I guess it could be that the m2 ammo I bought was not in fact m2 and it was able to bend it over the 4 clips.

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Old October 27, 2022, 10:34 PM   #2
4V50 Gary
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Did you grease the helix (cut out in the op rod that works the bolt) and the trackway the op rod guide works on?
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Old October 27, 2022, 10:41 PM   #3
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The load sounds too light. I probably wouldn't use federal primers, to avoid slam fire.

-TL

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Last edited by tangolima; October 27, 2022 at 10:48 PM.
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Old October 28, 2022, 12:51 AM   #4
nhyrum
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Quote:
Originally Posted by 4V50 Gary View Post
Did you grease the helix (cut out in the op rod that works the bolt) and the trackway the op rod guide works on?
I greased the track the op rod works in. I'm not certain what you mean by the helix, but if I'm thinking about the right thing, I believe so, I just don't have the rifle in front of me to get eyes on it to make sure I'm thinking of the right place.
Quote:
Originally Posted by tangolima View Post
The load sounds too light. I probably wouldn't use federal primers, to avoid slam fire.

-TL

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Yeah, the federals weren't my first choice either, but 1: they're what I had, and they are magnums so I believe they're harder(and why I started the load lower) and 2: it's all I can find, even online. The cci military ones are nowhere to be found.

The load appears light per the velocity, but the same load should Chrono 250 fps faster, and is near or barely over book max, so I'm hesitant to keep going up, but I did hear that some of the early m72 had up to 50 grains. The primers are starting to flatten, but that could just be the soft federals, so I'm also not to eager to run higher with them. What's puzzling to me though is it worked with the factory ammo before my teardown, and doesn't now, so I'm kind of thinking it's a mechanical issue, at a minimum.

My biggest concern is bending the op rod, so while I do enjoy my hand cannons and shoulder busters, I'm not very anxious to just keep bumping up the load.

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Old October 28, 2022, 03:21 AM   #5
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I can't give you numbers to check, but you might have a problem of a worn gas cylinder. Expand that idea to include anything lowering the effectiveness of the gas pressure. The piston op rod tip,etc.

If you got it from CMP, I'd expect it would be armorer evaluated as serviceable.If its a CMP gun,contact them.

Private sale , gun show or ? It could be anything. You don't know who may have done what.

I would not alter any parts. Whether you load it or buy it, I'd start with GI spec ammo. Velocity correct for bullet weight. I'm no expert, but 4895 is probably correct for 150 gr bullets. Maybe (I don't know) 4064 for 175's? Dont believe me! Check references. If you have a correct recipe, the chrono should show approximately GI correct velocity at GI correct pressure. . It might not run at 2400 fps. There is a balance to achieve.
No need to re-invent the wheel.

Give it a chance with proper ammo.
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Old October 28, 2022, 06:23 AM   #6
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Going from memory here, but I use 55g of 4064 under a 165gr boat tail over a standard CCI LRP. I later discovered it's considered a tad hot for the Garands, I believe, but I haven't had any issues with it.

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Old October 28, 2022, 10:49 AM   #7
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Cycling

1) 46 gr of 4895 using a 150 -175 grain bullet should have a velocity of 2700-2800 fps.
Not sure why your velocity is so low.
If you put the gas cylinder on and tightened the lock ring to the point the upper handguard is trapped and immobile, the gas cylinder plug may be partially blocking the gas port.
If you remove the plug, loosen the lock ring and look into the front of the gas cylinder, the gas port should be visible centered front to back in the opening in the gas cylinder that allows the gas to travel into the cylinder and push the piston.
Good luck
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Old October 28, 2022, 11:21 AM   #8
tangolima
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I went to check my load record. OP's 2450fps for 173gr bullet seems correct for the charge. So it is not too light.

He did shoot some ball ammo, and the rifle closed on empty chamber. It indicates under gassing. The bolt went back far enough to eject the spent brass but not far enough to pick up a fresh round.

First perhaps is to eliminate mechanical issues with op rob and action. Make sure no moving parts are rubbing against anything. That includes tip of the op rod (piston) inside the gas cylinder. Lubing helps but probably not such a big deal we are led to believe. Next to check the gas system to make sure no blockage or leakage.

Regarding the primer. I understand federal is the only thing available. But I would wait till proper components become available, rather than taking the risk. Slam fire on M1 happens rather frequently. It may be at the worst timing.

-TL



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Old October 28, 2022, 12:54 PM   #9
nhyrum
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The gun was a CMP gun, but I did not buy it from them, I bought it off GunBroker. As I said, the rifle functioned fine when I first received it on ball, but not after my disassembly.

The upper hand guard is immobile, so it sounds like I might have things too tight and not lining up.

Edit: took the gas plug out and loosened the retainer. The hole in the barrel is very close to the threaded end of the opening.

How tight should the gas plug be? I'd say I had it tightened less than you would torque an oil pan drain bolt or maybe about as tight as an oil filter. About the point where you actually need some leverage to turn it but not more than about two fingers on the wrench

The picture isn't the greatest angle and makes it look like it's half covered when it's not, but it's close.

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Last edited by nhyrum; October 28, 2022 at 01:22 PM.
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Old October 28, 2022, 04:58 PM   #10
jcj54
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M1 cycling

From your picture, it appears that if you loosen the lock ring 1/2 a turn and put the plug in you will be in the right place. The upper handguard should move slightly forward and back when gas cylinder is tight.
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Old October 28, 2022, 08:45 PM   #11
4V50 Gary
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Let's go back to the ammunition. After your reassembled it, does it still function with M-2 ammunition?

If yes, then it's your handloads. If no, then it's the M-1.

I'd be concerned about the gas cylinder. If either the gas cylinder or the its lock screw is too loose, gas pressure won't be sufficient (gas escape).
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Old October 29, 2022, 12:57 PM   #12
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It worked before you took it apart. It doesn't work after you put it back together....

The obvious is that it was something you did, or didn't do that causes the gun to malfunction.

We can't fix that from here, with no idea what you did or didn't do, other than "I followed some U Tube videos"...
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Old October 29, 2022, 02:53 PM   #13
4V50 Gary
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I remember trying to diagnose a problem online and it's like taking your pet to see the vet. The vet is reliant on the customer's observation skills and verbal communication skills (no insult to OP) to diagnose and treat the pet correctly. Sometimes you just have to see it for yourself.
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Old October 29, 2022, 03:24 PM   #14
tangolima
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I wouldn't say the rifle worked perfectly before disassembly. It short cycled 2 out of 40 rounds of ball ammo. It already showed tendency.

-TL

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Old October 29, 2022, 04:59 PM   #15
Scorch
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You don't tighten the gas block with a wrench, it is supposed to be sloppy-floppy until you put the plug in. Sounds like you are overtightening the gas block.
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Old November 6, 2022, 06:52 PM   #16
Jeremy2171
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Looks like a rack grade and that barrel looks rough.

Several issues there...I'd suggest sending eto a competent gunsmith. PM if you want info.
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Old November 6, 2022, 09:30 PM   #17
Logs
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The gas block should be tight where you go past the threaded hole a quarter of a turn and then go back and line up plug. (NOT super tight) If you have a hard time getting the plug out this little black tool is a life saver. I use this tool with a 1/4 socket extension. You can also get a gas plug from "GarandGear" that allows you to shoot modern 150 gr ammo. It also reduces a bit of recoil.




https://www.garandgear.com/the-m1-ga...al-ammunition/

Also my newest M1 had a bunch of rust on barrel and I took a brass brush and hoppe's solvent and got most of it off. Then I ran some Van's Gun Blue over it and it looks much better.

BEFORE>>>>>>>>>>>>



AFTER.....................




Still a bit of pitting, but much better than it was. Mine shoot great. Good Luck
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Last edited by Logs; November 6, 2022 at 09:36 PM.
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Old November 7, 2022, 09:12 AM   #18
Jeremy2171
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Quote:
Originally Posted by Logs View Post
The gas block should be tight where you go past the threaded hole a quarter of a turn and then go back and line up plug. (NOT super tight) If you have a hard time getting the plug out this little black tool is a life saver. I use this tool with a 1/4 socket extension. You can also get a gas plug from "GarandGear" that allows you to shoot modern 150 gr ammo. It also reduces a bit of recoil.
Couple clarifications....

There is no gas block..it's a gas cylinder.
There is no gas plug..it's a gas cylinder lock screw.

What year did ammo start being "modern"?

There is no 150gr weight limit on bullets.

There is no need to buy aftermarket parts to shoot your rifle.
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Old November 7, 2022, 10:04 AM   #19
Logs
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Try changing your magazine.....
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Old November 7, 2022, 10:12 AM   #20
jaguarxk120
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Has anyone else fired the rifle? There is
the remote possibility that you maybe
limp-wristing the rifle.
If not shouldered correctly the rifle will not cycle
correctly or miss feed.
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Old November 7, 2022, 11:30 AM   #21
tangolima
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Quote:
Originally Posted by jaguarxk120 View Post
Has anyone else fired the rifle? There is
the remote possibility that you maybe
limp-wristing the rifle.
If not shouldered correctly the rifle will not cycle
correctly or miss feed.
It is a gas operated semi auto. It works even if it free recoils.

-TL

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Old November 7, 2022, 01:47 PM   #22
jaguarxk120
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I'm very sure even a gas operated rifle/shotgun will
malfunction if limp/wristed.

Please note the M1 was designed to use one type of cartridge.
With a certain port pressure, changing the cartridge loading
will change port pressure and operating rod speed. Also note the operating rod is under pressure for a very short length of time and after the bullet leaves the muzzle the rifle cycles as a recoil type of rifle using the inertia of the operating rod and bolt to complete the cocking/loading cycle.

Last edited by jaguarxk120; November 7, 2022 at 02:03 PM.
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Old November 7, 2022, 08:11 PM   #23
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@Jeremy2171, nice job with the correct nomenclature.
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Old November 8, 2022, 11:57 AM   #24
thegatman
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Nobody mentioned changing out the op rod spring. I had the same problem and after changing out the spring,it worked fine even giving me the classic ping
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Old November 8, 2022, 01:36 PM   #25
Jeremy2171
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Quote:
Originally Posted by thegatman View Post
Nobody mentioned changing out the op rod spring. I had the same problem and after changing out the spring,it worked fine even giving me the classic ping
A new oprod spring doesn't fix short stroking.
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