Winchester Super X1 not cycling

[Jenrick]

I recently purchased a Super X1 off of gunbroker, the seller advised the bolt would only partially cycle when fired, not ejecting the hull. I received the gun yesterday and broke it down to clean it. The buffer appeared to be in good condition, showing very little wear. The return spring follower is an unusual design that doesn't match any of the parts I'm seeing online. It's a 4 digit serial number gun, so it may be an early production part that got changed later. The follower is missing the pin, but it doesn't appear to have any issues with sticking or tilting, as hand cycling the bolt is extremely smooth.

The gas system was rusty and pitted. I am planning on potentially replacing the majority of it if need be. The rubber o-ring is missing chunks, and I have some replacements. I did have a question regarding gas piston head, what does it do? On this gun it is firmly rusted in place, and am I currently soaking it in oil to see if I can free it up with some heat tomorrow. I am however not sure I understand why it's a sperate part? Would it being stuck in place be part of the reason the gun is not cycling? I'll test fire it with the new o-ring tomorrow and see if that has any change in function.

Test firing the gun, the bolt does not cycle at all, it is firmly in battery locked into the barrel extension with the hammer resting against it. Hand cycling the gun will clear the chamber, eject the hull and feed a new shell perfectly fine. It appears that the gas system is getting either no gas or not moving at all.

 

[351 WINCHESTER]

I bought a new one back in the day and it would jam with full power buckshot loads. Someone told me it needed a new gas o ring. I would try that first.

 

[Jenrick]

So it turns out after I finally got the piston head off, it is missing the inner piston ring. This ring is what actually creates the gas seal to allow the gas system to function. Got one on order, so that should hopefully solve that issue.