ULT Question

[nak81783]

I just want to make sure I have this straight. The ULT works by decreasing the diameter of the On/Off Pin exposed to pressure. That is also what reduces the reactivity.

Is that right or am I missing something?

Can someone take a pair of calipers or micrometers and tell me what the dimension of that top diameter is. I know WARPIG stated the skinny part is like 0.035", but what's the top part of it?

Thanks,
Nathan

[Jerhew]

the top part is apparently the same size as the current x-valve on/off pin top...
they use the same size o-ring...
i don't have a mic to measure how big that actually is though...

[nak81783]

Really? That doesn't make sense to me now. It seems the top of that pin should have to be smaller if it's going to reduce trigger pull. Less surface area under the same amout of psi equals less force required. Or something like that. Anybody else with anything to add? I'd really like to get a diameter with a measuring device.

Thanks,
Nathan

[Jerhew]

the top is the same the bottom is smaller

http://www.automags.org/forums/showthread.php?s=&postid=954477#post954477
there's a decent pic of all the parts here
and if you read the caption black explains which orings are which and what they're the same size as...etc

doesn't really make sense to me either but i haven't taken an fluid dynamics classes in years:D

[Jerhew]

actually no im wrong
its the same size as the center o-ring on a regular on/off assembly
so that means the top of the new on/off pin is the same size as the small end of a regular rt/x on/off

[nak81783]

OK, thanks for all of your help.

Thanks,
Nathan