|VM Empire Where the VM-68's and PMI-3 Come out to play|
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|05-29-2012, 09:09 AM||#1 (permalink)|
Join Date: Apr 2012
VM needs help
So I took the VM out for a bit at the field this weekend. I tinkered with it as I could but the gun never fired right. Cock it back pull the trigger and got nothing. I was using a 68/45 CP hpa tank. Output was over 800psi. Any ideas of what to look for? There were no leaks.
Demonic Cocker No.4
|05-29-2012, 12:01 PM||#2 (permalink)|
Join Date: Aug 2009
When you say nothing happens do you mean the hammer strikes the valve and no air comes out?
Or some air comes out but not enough to reset the hammer?
When you dry fire it should move with enough force to move the gun. I'm guessing that it's sticking or slowing down between the reset and the valve.
Pull the bolt and hammer assembly out and check if there is any oring damage and/or crap around the hammer and lower tube.
Pull the valve and make sure the stem of the cup seal doesn't have nicks that could cause it to bind when struck.
Put your mask on and with the valve out and the back of the gun pointed at the wall, screw in your tank slowly to see if gas comes out. If it doesn't then there is something blocking the air hose or ASA.
Lube the stem, bolt and hammer orings and see if it feels stronger when dry firing.
Then gas up and try again.
If it still doesn't fire then your input pressure is way above the 800psi and you should try with a CO2 tank.
|05-30-2012, 10:03 AM||#3 (permalink)|
Join Date: Aug 2006
Location: Southern Maine
If nothing at all happens?
Well, obviously the tank could be empty. I've made that mistake a few times. ie taken the gun apart, check everything... a few times before I realized I had an empty tank.
But other things can cause that. An obstruction on the bolt, like a broken shell, or broken fingers can cause that. Or if you have a port-screw that is too long, hitting the bolt.
For the hammer, a common mistake is to replace the 10/32 valve screws with the longer ones used for the panels. They push against the cupseal and keep it from moving. Likewise, some aftermarket cupseals were 2-piece. They could become seperated, and lodge itself in front of the hammer.
And might be the ASA. Some VM asas had a small depressor. If the HPA tank also had a small pin-valve, its possible that they just don't make enough contact to open the valve? Like said above, you can tell that by gasing up with the valve removed to see if it at least gets pressurized.
BUT, if it does at least "pop" when you pull the trigger? But not enough to recock? Similar issues as above. Likely there is an obstruction. Sometimes you can isolate by first removing the bolt, and see if the problem goes away. Does it still have the spring guide? what parts are still original?
"the evidence strongly suggests that neither Billy nor Adam (Smart Parts) could have invented the electronic paintgun" -Garr M. King, U.S. Judge
|06-02-2012, 01:23 AM||#4 (permalink)|
Join Date: Mar 2009
Location: Ottawa, ON
Check for swollen bolt o-rings - they can create enough drag to cause the symptoms that you have described... Good luck.
Unfortunately "want" and "need" are two very different things...
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