Xvalve ULT Setup

[Drego]

I went out and bought the hyped ULT on/off for my Tac One. I installed it right out of the box and had shootdown. I've read everyone's experience with setting it up and it just didn't make mine right. I contacted AGD tech and he pointed me to two seperate but distinct problems. First off he told me that at a minimum, my Lvl10 had to have 3 shims in it. I went back to my setup and because of a barrel leak, ended up removing them and installing a smaller carrier. I went back and corrected this issue and still had to go down a .5 carrier from that installed with 3 installed shims in the Lvl10. No shootdown or barrel leaks and all is well. The AGD tech told me that the ULT should have 6 shims installed for it to work in My Tac One and it worked with 5 shims but had shootdown and installing the 6th shim, I couldn't slide the valve all the way in to the mainbody. Seems the pin or something is making contact with something and the valve can't be fully seated in the body. Remove the 6th shim and the valve seats but have the shootdown issue. Anyone else experiencing this same sort of scenario and have any workarounds for it? I thought I purchased an item that was plug an play, but obviously not. Before I flush this wasted money down the toilet, maybe someone can pipe in with some useful info. I've also got a question about the on/off and why so many shims are needed? Why can't it just be one .50 shim and then you add on from there? Something like the carrier for the Lvl 10 would make it much more simplier and adapatable for those of us fine-tuning. I'm not impressed at all with the ULT for it's price or performance so far! Guess another call to AGD is added to my to-do list today.

[athomas]

Using 3 shims in your level 10 is part of your shootdown problem. You are having to use a tighter carrier to stop the leaking. That slows down the bolt cycle and reduces the charge time for the valve.

Always use the largest carrier that doesn't leak. Check this without any powertube shims installed. Level 10 shims in the powertube don't affect how the ULT operates.

The ULT adjustment works by pushing the top oring up as you add shims in the ULT. This simulates a shorter on-off pin which shortens the timing distance between the bolt sear and the on-off, which reduces drag, so it helps with the resetting of the assembly after a shot. If you put too many shims in, you can squeeze the oring against the top which will cause the oring hole to tighten and it will introduce more drag on the pin instead of reducing the drag.

In your setup, I wouldn't use any more than the 5 shims you are using. Also, try not to mix up your level 10 and your ULT shims. The level 10 shims are .010" thick and the ULT shims are .005" thick. Putting a level 10 shim instead of a ULT shim, is the same as adding 2 ULT shims.