How to grind down .750 on/off pin?/Serious shootdown with emag onoff in classic valve

[halB]

Okay. I can accept that this needs to be done. But I need to know WHY it has to be done. Tom Kaye is a god. I can't imagine why the pin that he designed for an RT valve won't work in a classic valve with the proper on/off. I know all sorts of people drop it into their set ups. Why are my three valves different? (Odds are it is this on/off that is different, I doubt any differences could be found amongst these three valves)

[blackdeath1k]

Why ask why. I couldn't believe 2 100ths of an inch kept my gun from cycling. But you can look up my minimag thread from a month or so ago. And that was the result of my fight to get my wife's gun to work. Stock rt on off and pin in a classic mag. Pin was .769. It would not cycle at all till I got to .75. Then it worked fine.

My best explanation to the minuscule change in gun valves is the tiny variation when they mill the on off hole in the valve body. But I can't really tell why.

[athomas]

You have three valves that don't work with this pin. Did you use the valves in the same gun/body/rail? Do you have the rail bushing installed?

[halB]

Tried it on a ULE body, tried it on my body that's worked for years and years. Tried it on a new rail/sear, tried it on my trusted rail/sear. Yes, had the bushing installed. (found out how important that one is because I'm trying to get rid of bolt stick on one of these classic valves, but one problem at a time.)

Maybe we should start from the beginning. Am I supposed to use everything from the x-valve assembly? The upper and lower housing, the o rings, including the quad 004?

[Justus]

Tried it on a ULE body, tried it on my body that's worked for years and years. Tried it on a new rail/sear, tried it on my trusted rail/sear. Yes, had the bushing installed. (found out how important that one is because I'm trying to get rid of bolt stick on one of these classic valves, but one problem at a time.)

Maybe we should start from the beginning. Am I supposed to use everything from the x-valve assembly? The upper and lower housing, the o rings, including the quad 004?

On my first X-valve, I couldn't get the thing to rapid fire at all with a .750 pin. I had to go shorter.

If you're not using Emag lowers, you can replace the quad o-ring with a 006 urethane o-ring. And if you are using Emag lowers, your pin is way too long anyway (should be .712).

[halB]

Classic rail (choice of 3), powerfeed body/ule, intelliframe/cf frame/homemade frame.

[halB]

I guess we'll never know. Last thing i did was I changed out the quad o ring for the 006 teflon, and there was about as much improvement as when I put the spacers in there. I then ground the hell out of it, to a flawless .712 or .713, using a dremel. Thanks Justus, it was pretty easy once I had the confidence.

Put the pin in my emag valve, and I believe it is working. Seem to be getting some bolt stick when shooting fast, but whatever, my tank only had 500 or 600 psi in it. Just wanted to make sure it didn't leak. Once I fill up my tank I'll let you know how it's doing.

[athomas]

Maybe we should start from the beginning. Am I supposed to use everything from the x-valve assembly? The upper and lower housing, the o rings, including the quad 004?

All on-off parts need to be transferred to the classic valve. The quad oring can be changed out to the urethane oring. The quad oring requires the use of a shorter pin.

If you use the quad oring in the emag, use the 0.712" pin length. It will work fine in the classic like that as well.

You will get some shootdown and chuffing with low pressure from the tank. The level 10 operation requires a higher input pressure to the valve in order to work properly.