PMC Plainfield-USGI parts compatibility problems

[painter777]

Thought I'd pass this along as many think most all parts are interchangeable between Plainfields and GI carbines.

Friend of a friend referred me to look over/repair a Plainfield carbine for him.
All PMC except having a real USGI C tip sling.

Original concern was FTF. Primers were being dented, but old ammo and had been reloaded. COAL'S WERE ALL OVER THE MAP.
fOUND THAT THE FIRING PIN SEEMED TO BE TRAVELING FAR ENOUGH BUT WAS BINDING heavily WITH THE EXTRACTOR AND EJECTOR.
The original PMC trigger housing shows a chipped inner edge on the left rail where the hammer would rest after being released.
Sometimes completely missing the trigger housings left rail stop and traveling forward falling partially between the trigger housing walls.
Causing it to hit the upper right rear side of the bolt but barely catching the rear of the firing pin.

Replaced that housing with a UEF t4 housing.
Put all the original PMC parts back in, except replaced the hammer and trigger pins with GI.
Found that the Hammer and trigger pins for the Plainfield housing need to stay with it. (different lengths than GI.)

After putting back in the original PMC hammer I could see too much side to side movement.
Dry firing it could cause it to walk sideways to the right and go beyond stop position, sometimes missing it's resting edge on the left rail of the USGI housing.
Compared the thickness of the PMC hammer to a GI and found the PMC to be much thinner.
Installed a GI hammer and all was well.

So after un-binding the ejector/extractor and firing pin and doing a complete thorough cleaning, it ran like a clock today.

I'm posting this 'Commercial Carbine Info Here' because of it's interchangeable parts with USGI.
Just something you might want to take note of.

Thank You,
Charlie-Painter777

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