Full Auto w/ ULT

[jrod]

I got a used ULT and am trying to install it into an x-valve. With no shims, I am getting full auto. I have tried this with two different x-valves installed in two different automags. Any thoughts?

[Tunaman]

Measure the pin. It should be .740 or very close to that.

[jrod]

It looks like it is bent slightly. Would that be enough to cause the full auto?

[athomas]

If it is bent, it is probably not sealing properly. A continuous supply of air would allow the bolt to continuously cycle if the air flow was high enough. ie full auto

[jrod]

Just to be clear, it is full auto only when I pull and hold the trigger all the way back. I can get a single shot with a partial pull and release of the trigger.

[Ando]

Did you oil it? I had a valve that does that when it needs oil. I wish all my valves did that

[athomas]

Just to be clear, it is full auto only when I pull and hold the trigger all the way back. I can get a single shot with a partial pull and release of the trigger.

As long as the sear is forward, it can't fire. It would only go full auto when you pull the sear back and push the bent pin up into the oring. It would have both conditions satisfied when the trigger is held, the bolt is free to go back and forth, and the on-off is allowing air to flow past it.

[jrod]

As long as the sear is forward, it can't fire. It would only go full auto when you pull the sear back and push the bent pin up into the oring. It would have both conditions satisfied when the trigger is held, the bolt is free to go back and forth, and the on-off is allowing air to flow past it.

So this is a function of the bent pin? I guess I'll need a new one if I can't get it straightened (time to contact Tuna).

[rawbutter]

So this is a function of the bent pin? I guess I'll need a new one if I can't get it straightened (time to contact Tuna).

So... you want to send the bent pin to me when you take it out?

[athomas]

So this is a function of the bent pin? I guess I'll need a new one if I can't get it straightened (time to contact Tuna).

If the pin is actually bent, it will cause the problem you are having. You can try to straighten it. Once straightened, you can roll it on a flat surface. A mirror works really well. You can see if it has any wobble. If it has any wobble at all, it is not straight yet.

[jrod]

Problem solved. I'm missing an o-ring.

[athomas]

Yeah, that'll do it.