M1 garand gunsmith
- Thread starter dxn
- Start date
There is a well defined list of stoppages/malfunctions with these rifles along with matching corrective actions. Most fixes involve replacement of worn parts and improving metal to wood fit. There are manufacturing and wear tolerances on parts, so some selective fitting is usually necessary for corrective functioning. Wear/failure malfunctions often occur with the gas system - worn gas cylinders, worn op rod pistons, insufficient gas feed thru gas port, leakey gas plugs. Weak/worn op rod springs are a common problem.
You should describe the nature of your problem. Unfortunately, sources of replacement parts have pretty much dried up.
You should describe the nature of your problem. Unfortunately, sources of replacement parts have pretty much dried up.
Joe Amorosi
CGN Regular
- Location
- Not Where I Thought I Was....
Take the op-rod spring out, put the stock back on and do a "Tilt" test. Your op-rod may be binding.
Do try the tilt test, but also try another en bloc; they do wear. Also, try loading the en bloc with the top round on the left instead of the right.
If the bolt isn't picking up the round you could have an insufficient gas problem. Check the gas plug for a crack in the face and make sure that it seats fully. Also, clean the gas port in the barrel. The gas port should be fully visible thru the opening in the gas cylinder. The gas cyl should also be clean and free of excess powder fouling.
Beyond these things, the pistion on the op rod may be undersize or the bore of the gas cyl could be oversize. The piston should gauge .525 diameter. The interior dimension of the gas cyl can be checked with plug gauges. Make sure the chamber is free of powder fouling which can delay extraction and bolt travel. It needs to be cleaned with a brush and solvent.
Early/late bolt release on a loaded clip may indicate a timing problem. This can often be remedied by changing the bullet guide for one with a higher fulcrum. Fulcrum height can be checked with a micrometer; min/max is .175- .183. Again, try loading with a different en bloc.
I recommend the Scott Duff book, "The M1 Garand Owner's Guide" as a helpful reference.
P.S. The rifle must be lubed with suitable grease on all specified lube points
If the bolt isn't picking up the round you could have an insufficient gas problem. Check the gas plug for a crack in the face and make sure that it seats fully. Also, clean the gas port in the barrel. The gas port should be fully visible thru the opening in the gas cylinder. The gas cyl should also be clean and free of excess powder fouling.
Beyond these things, the pistion on the op rod may be undersize or the bore of the gas cyl could be oversize. The piston should gauge .525 diameter. The interior dimension of the gas cyl can be checked with plug gauges. Make sure the chamber is free of powder fouling which can delay extraction and bolt travel. It needs to be cleaned with a brush and solvent.
Early/late bolt release on a loaded clip may indicate a timing problem. This can often be remedied by changing the bullet guide for one with a higher fulcrum. Fulcrum height can be checked with a micrometer; min/max is .175- .183. Again, try loading with a different en bloc.
I recommend the Scott Duff book, "The M1 Garand Owner's Guide" as a helpful reference.
P.S. The rifle must be lubed with suitable grease on all specified lube points
Last edited:
Joe Amorosi
CGN Regular
- Location
- Not Where I Thought I Was....
Did you get your Garand from Nick at Vulcan?
He has been known to refurbish old worn out gas cylinders. He hones them out slightly larger that milspec and then welds an oversize piston to the end of the rod. If you have changed your op-rod (with a milspec piston) this could be your issue.
As Purple said... Not enough gas...
Joe Amorosi
CGN Regular
- Location
- Not Where I Thought I Was....
I have to ask..... How did you bend your op-rod?
Please forgive me for asking but, are you aware that op-rods aren't strait to begin with?
They have specific bends in certain places from factory to facilitate smooth operation..
Please forgive me for asking but, are you aware that op-rods aren't strait to begin with?
They have specific bends in certain places from factory to facilitate smooth operation..
I am aware op-rods aren't straight. I suspected it was bent only because the action was jammed up.
I send it to my local gun store, who miraculously had a new op-rod. And it fixed the issue, I just needed to get an adjustable gas plug to fine tune the cycling.
