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Ebbed
10-16-2009, 03:57 PM
I need some suggestions to keep my pneumag from short stroking. It fires SO CRISP but when I'm to early on the pull it short strokes. I should tell you I am using a ULT, and some people have reported problems with this, setup. However both p-magger and zap agree the ULT can work very well with a pneu seup.

vf-xx
10-16-2009, 04:04 PM
How many shims are you using?

Ebbed
10-16-2009, 04:42 PM
in what my ULT or my lvl 10? If i had to guess i would say 4 or 5 in my ULT. none in my LvL 10 since i went down a carrier size.

vf-xx
10-16-2009, 04:49 PM
ULT.

My understanding of it is that the shims change your total effective on/off pin length.

More shims = shorter pin = more reactivity, implying a softer pull

less shims = longer pin = less reactivity, implying a stiffer pull.

You might try pulling out a shim or two and see what happens.

ZapTheMad
10-16-2009, 08:33 PM
A little more pressure in the pneu's might help. The RT effect pushing back on the system is fairly strong. Might try lowering the gun input pressure a little too (if you have an adjustable tank). Somewhere in there is a sweet spot that rips.

Ebbed
10-16-2009, 08:50 PM
For the sake of simplicity i have ordered a R/T on/off. Ill let you all know how it goes.

chafnerjr
10-17-2009, 07:13 AM
Pay attention to all of the above... but, do you have a magnet mod? A magnetic trigger return lets you fine tune your pull a little more because you'll have something to force the trigger back out fully before your next pull. Just a thought. :cheers:

Ebbed
10-19-2009, 08:04 PM
Since i have jumped ship and went over to the R/T side, anyone have any suggestions for a tank output pressure for my pne setup? I'm thinking 1k output might be a little heavy. Remember I'm aiming for no short stroking. I'm willing to sacrifice some trigger pull for it. No matter what it will still be lighter than the ULT which was my objective.

chafnerjr
10-19-2009, 10:14 PM
I'm no airsmith... but I'm pretty sure you can't RT a pneu... can you? I would think that there's no way to transfer the back pressure from the on/off to the trigger given that it's run through a 3-way. Correct me if I am wrong. Either way, best of luck. :cheers:

Spider-TW
10-19-2009, 10:28 PM
I'm no airsmith... but I'm pretty sure you can't RT a pneu... can you? I would think that there's no way to transfer the back pressure from the on/off to the trigger given that it's run through a 3-way. Correct me if I am wrong. Either way, best of luck. :cheers:
On any one day, if you have a reactive RT trigger with pneumatics you may be able set the lpr so that the marker will RT whenever the trigger is held down. It's more like a full auto trigger, and it can wonder off as the lube and pressures change, at least on the one I have seen. The pressure to the ram is balanced by the ram return spring and the sear RT, just like your finger would be. It's interesting, but entirely impractical.

Ebbed
10-20-2009, 02:16 PM
Perhaps i was unclear. I don't intend to get RT bounce with my pneumag. I'm simply switching to a RT on/off to reduce short stroking...

athomas
10-21-2009, 04:09 PM
How is your level 10 setup? Anything that slows down your bolt cycle, will help induce short stroking. The other thing to check is how far the on-off is allowed to open. The farther it opens, the faster the chamber recharges, and there is less chance of short stroking.

Ebbed
10-21-2009, 04:46 PM
My lvl 10 will need to be re-tuned. I went DOWN a carrier size during my fiddling. The first time it was set-up it had a carrier that was too big, and shims were put in place to stop the leak (4 of them). As I removed shims the leak got worse and worse, so I decided to go down a carrier. I hope that answers your question.

Now my question is this:
If at 1000psi+the RT valve is super reactive, and 850psi is your stock tank output, If I dropped mine to 750- 800 would I still have a super fast recharge with little to no trigger activity? I honestly believe my poor walking skills mixed with the ULT was causing a lot of my problems. That’s why I ordered the R.T On/Off for my pneumag. Like I mentioned before I’m willing to sacrifice some trigger lightness in exchange for little to no short stroking. I firmly believe the new set-up will still be considerably lighter than the ULT alone before pneumatics.

athomas
10-21-2009, 10:09 PM
My lvl 10 will need to be re-tuned. I went DOWN a carrier size during my fiddling. The first time it was set-up it had a carrier that was too big, and shims were put in place to stop the leak (4 of them). As I removed shims the leak got worse and worse, so I decided to go down a carrier. I hope that answers your question. Adding shims doesn't stop leaks. Removing them might help if too many shims are causing the vent hole to be exposed while sitting at the reset position. Always do your tuning without any shims. Shims don't affect the performance or bolt stick. They only allow you to adjust the reset point.