Plainfield M1 Carbine: USGI vs Non-USGI

[MarineOne]

Hey folks,

I picked up a police department purchased M1C a while back and I'd like to get the Ultimak rail for it as it will be the camp gun and HD weapon, but they warn against using the Plainfield because it's not USGI.

How do I go about telling whether it's a USGI gun or not? I've had it apart and believe that it is, but how would I go about confirming this?

If not, can I just get an aftermarket stock or a surplus USGI stock, or is there something specific that would prevent me from doing this?


Thanks!



Kris

 

[Slamfire]

but they warn against using the Plainfield because it's not USGI.

A shooter in my club wins our Carbine matches with a plainfield. It has a better barrel than GI carbines.

I suspect the warnings against the Plainfield have no basis in reality. Someone was confused or spiteful,started a rumor, passed it around, in time in that closed society, it became an "accepted fact". But is it probably based on nothing but hearsay going around and around and around.

 

[Snakum]

I suspect the warnings against the Plainfield have no basis in reality. Someone was confused or spiteful,started a rumor, passed it around, in time in that closed society, it became an "accepted fact". But is it probably based on nothing but hearsay going around and around and around.

+1

I have worked on and shot (extensively) two of the much-maligned Iver Johnson M1Cs for friends that ran far better than the three USGI models in our now-disbanded little shooting group. Of the three USGI models not a single one has ever gotten thru a 30 round mag without jamming, while the IJs will, about every other session. But when I started reading up on them to work on the first one, you'd have thought it was guaranteed to blow up and kill me with every shot. Some of the crap that gets around on the errornet is amazing.

No doubt some Nimrod will along shortly ranting and raving that the Plainfield/IverJohnson/Universal is just a deathtrap waiting to to blow up and that his first cousin's nephew's stepmom knew a guy who merely looked at his Plainfield carbine resting in the gun safe and it promptly blew up and killed him and three family members and blinded the family dog and started a fire that burned down the entire neighborhood and their town then sank into a swamp.

See the sig ...

 

[Balrog]

How do I go about telling whether it's a USGI gun or not?

If it is a Plainfield, it is not USGI. Plainfield never made M1 Carbines for the US government.

 

[wcwhitey]

I had a Plainfield for a while. Very good shooter. I didn't put it through any torture tests but the barrel was mint and some of the parts were USGI. Good ammo was abound and it ate everything I threw at it. As long as the price reflects the lack of pedigree I would buy one again without hesitation. Bill

 

[Shear_stress]

If it is a Plainfield, it is not USGI. Plainfield never made M1 Carbines for the US government.

Not for the US military, but Plainfield did sell a bunch of carbines (including full-auto M2-type weapons) to US (like the OP's) and Korean LE agencies. Many Plainfields were also exported to the armed forces of some South American countries.

http://www.m1carbinesinc.com/carbine_plainfield.html

 

[amd6547]

Plainfields were good guns, but I wouldn't say their barrels "are better than GI"...My CMP Inland has an Underwood barrel that shoots tight groups at 100yds...tighter than the Plainfield I used to own did at 50yds. Besides, when comparing GI carbine barrels to a new commercial Plainfield, what was the muzzle wear like on the GI?
As far as GI carbines not getting through a 30rd mag without a jam, were they equipped with the M2 mag catch made for the 30rd mag? My Plainfield was about 90% M2, lacking only the full auto trip lever and switch...that is how they built them. It did have the M2 mag catch.
Iver Johnson carbines were built with Plainfield tooling. They can be great or terrible. My shooting buddy bought an Iver after shooting my Plainfield...After about 100rds, the cam surfaces in the op slide were worn away...they had not been heat treated.
I would not trade my CMP GI carbine for anything.
If I had to own a commercial carbine, it would be a Plainfield. I absolutely would not own a late-model, stamped op-slide Universal.

 

[Carl N. Brown]

Plainfield Machine Co. made carbines for the the US civilian market--police, hunters, self-defense, collectors who couldn't find a military issue carbine, etc.

Plainfield was not USGI in the sense of military issue, but of the civilian market carbines I have seen, they seem to be USGI in the sense that they are military specification.

The Universal carbine started out mil spec, but ended up a complete redesign with hardly any mil spec parts: that gun may be what some have in mind in saying civilian carbines are not USGI.

Volunteer Arms (Commando Arms) of Knoxville made "tommy gun" stocks for the M1 carbine (the stocks were fixed butt Mark I, no butt Mark II and detachable butt Mark IV) and warned their stock would not fit the Universal, but would fit military spec carbines including the Plainfield.

 

[Trebor]

The Planefield is not a USGI carbine.

The Ulitmak rail may not fit in as the internal clearance in the Planefield stock is different then a USGI stock. Of course, you can always install a USGI stock or relieve the wood on the Planefield stock.

The Italian stocks on the new CMP Italian carbines also won't work with the Ulitmak rail.

 

[MarineOne]

Trebor,

That's what I thought, but wanted to make sure that was the only difference.


Thanks for the info



Kris

 

[carbine85]

The later Plainfield and Iver Johnson Carbines simply are not on par with the USGI Models. They are good rifles but they don't measure up to the USGI.
I have a Iver Johnson that I'm refinishing right now. It's not even close to USGI.

 

[CZguy]

I have a Iver Johnson that I'm refinishing right now. It's not even close to USGI

Could you elaborate on this? In what respects is it inferior the USGI?

 

[bigfatdave]

Notes on fit; The UltiMAK M6 optic mount will not fit, and cannot be modified to fit, Carbines manufactured under the name "Universal" and some Carbines made by Plainfield. If you have a Universal or a non-mil spec Plainfield Carbine and you want to enjoy the benefits of the M6 forward optic mount, it is advised that you trade it for a G.I. pattern carbine. Either a 1940's vintage or the more recent production IAI, IMI, or a new Auto Ordnance Carbine will perform better and will be compatible with all after-market stocks and accessories.

The UltiMAK M6 when installed, should touch nothing but the barrel (should not touch the barrel-band or the receiver)(see photo; bottom right). We now offer two models, as some of the Auto Ordnance Carbines require a shorter mount. If you have a vintage Carbine, an IAI, or an IMI Carbine, you'll want the M6-B. Since the length of the mount is partly determined by the stock and the barrel-band clip, you may still want the M6-B if you're using an after-market stock on your Auto Ordnance Carbine. Simply measure the distance between the barrel band and reveiver, and get the model that's closest to, but still less than, this measurement. If you find your new optic mount too long or much too short, we will be glad to exchange it for the other length.

UltiMAK Forward Optic Mount
for U.S. Carbine, Caliber .30, M1
Fits G.I. pattern M1 Carbines.*
Cantilevered design.
Clamps securely to barrel in front of gas block.
Comes complete with screws, 4140 steel clamps, wrench and easy instructions.
Aluminum construction.
Finish: Hard anodized, non-reflective black matte.
Length; 8.055" (~8 & 1/16")
Model: M6-B

UltiMAK Forward Optic Mount
for most Auto Ordnance Carbines
Same as M6-B, but shorter in length.
Cantilevered design.
Clamps securely to barrel in front of gas block.
Comes complete with screws, 4140 steel clamps, wrench and easy instructions.
Aluminum construction.
Finish: Hard anodized, non-reflective black matte.
Length; 7.812" (7 & 13/16")
Model: M6-S

Based on these specs and the other info on UltiMAK's website, I'm wondering if the gas block or hand-guard dimensions are different on the carbines not manufactured to mil-spec.

Have you called the company and asked them? Seems like they could tell you what the difference is faster than random posters here. Unless you have a GI-issue model to compare to, that is.

 

[Carl N. Brown]

Short form: the Ultimak rail mount requires a strictly military spec barrel contour.

The rest of the carbine (action, stock) could be general issue, military specification, but if the barrel isn't, the Ultimak will not fit.

That is the Ultimak issue: not USGI fit and finish, but mil spec barrel outside dimensions.

Added: to some of us, USGI means military specification (parts interchangeability) but to others of us, USGI means the materials, fit and finish associated with WWII Winchester or Inland production.

 

[carbine85]

Could you elaborate on this? In what respects is it inferior the USGI?

Along with what's all been mentioned above a lot of them came with aluminum trigger housings. Some of the pins vary in size and have a sloopy fit. The bluing isn't up to par with the parkerizing. The commercial steel hand guard is junk and usually requires bending to keep it fitting tightly. When you look at the small parts side by side with USGI parts you can see where the commercial rifles cut corners. They make good shooters but I will gladly pay more for a nice USGI Rifle.

 

[Snakum]

Could you elaborate on this? In what respects is it inferior the USGI?

The IJ/Uni parts are lighter and likely crap metal in many areas. Example ... a USGI has a heavy, well-fitted charging handle/bolt carrier, whereas the IJ/Unis sometimes have a break in the corners of the cut outs from using stamped pot metal. The heat shield on the IJ/Unis is thin and flimsey and usually ill-fitted. Lots of things like that. The later examples deviated farther from US milspec and good metals than the earlier stuff. As near as I can tell the barrels were not as uniformly rifled end-to-end and likely again ... crap metal.

But all that said, you still have to maintain a USGI M1C and keep parts up and have good mags, or it will be a jam-omatic. And at the same time an IJ/Uni M1C copy can be picked up for a song and made to run very reliably. The USGIs in our group are not maintained and they run like crap. They are not magically "better" than any of the copies. Gotta keep em up.