Mike I should be able to get that bolt in your hands next week.I'm surprised that you are going with an xp style valve vs a mini valve, especially since you're building a tanker. IMO the only reason to run an xp style valve is to retain 12 gram capability, which for a while was important to me. A mini style valve will flow more efficiently I believe.
I believe I'm to the point where I have a stable design. I made 2 adjustments that will allow a more broad range of preload adjustment. I shortened the brass portion of the spring guide to 1.5", which will allow a little more preload. I also used thin 10/32 nylon lock nuts which will allow for less preload. Hopefully this will allow a stock qb spring to be used, which should reduce the shopping list for anyone wishing to build a similar design. I am doubtful based on previous testing, but I will test this weekend to confirm.So now it's time to start equipping the rest of the fleet....remember, nothing but a hacksaw or grinder and a hand drill are required to make this version. Gap is set during assembly, preload can be adjusted just like when using an RVA, except counter clockwise increases preload, clockwise decreases preload.