Saginaw SG Gas Piston - question

Just got a wide skirt Saginaw bbl and found the gas piston to be frozen in the aft position. The piston nut could be easily unscrewed but the piston remained frozen in place. After soaking in bore cleaner the piston will now move rotationaly,but cannot move it forward to remove it. Someone had clearly put a plier/vicegrip on the piston in an attempt to remove it as the end of the piston is deformed.

I note that the piston appears to be held in place behind a brass washer or retainer. The books make no mention of this retainer and only show the piston and the piston nut which retains it in place in the gas cylinder. I'm wondering if this brass retainer is unique to the Saginaw bbl and how to remove it as I wish to replace the piston. I'm now soaking the cylinder in Kroil. TIA.

The piston nut (Retainer) shouldn't be brass. It should have three notches in it that a specially piston nut wrench with three matching lugs that is hollow to go around the piston and engage the piston nut. It is standard right hand thread.

Right. I removed the piston nut with no difficulty,but the piston appears to be held in place by another brass washer/collar type of retainer. The piston rotates freely in this brass piece,but it will not move forward. It also appears that the gas port into the barrel is blocked as none of the fluids that I've put in the gas cylinder have drained into the barrel.

Just guessing......
Almost sounds like someone placed a Brass Compression fitting in there, like used on plumbing valves.

Anyway to get a close up picture?

Charlie

I have had one that had a hard carbon ring in this area right behind the nut.
I had to chip it oot with a small screw driver to rempve this piston.
That may be what you are seeing.

I wonder if it is jacket gilding (sp?) material mixed with carbon.