Help! Serious reliability issues w/ a mag classic

[mountainbob84]

I posted this as a reply to another thread but am reposting here it in the hopes of getting some more Ideas.
I purchaced a mag about six months ago,used and I heve yet to get it working satisfactorily. The Problem is something like this. I have a mag classic (one star), Smart parts barrell, macroline, expansion chamber and a double trigger and CO2. When I gas the gun up, It works fine for about two to three shots And then the shot consistancy goes to hell, shortly followed by the gun ceasing to work all together. When the gun quits, the trigger fails to recharge though there is no hiss of gas down the barrel like when the trigger is held back,. The only remidies I have found are to de-gas and then re-gas the gun (more than inconvienient in a fire-fight) or (in only about 1/3 of the instances this works) give the back of the regulator a hard whack with the palm of my hand. This last bit would indicate to me that something is sticking, but what. I put so much oil through the darn thing it is literally dripping out when I screw the reg apart. Temperature has no bearing on the problem as I have tried it in both hot and cold weather and the result is the same. The On-Off is installed correctly and I recently replaced the reg seat in a desperate attempt to fix the problem. Nothing has worked.
It is not uncommon for there to be an air leak near the back of the regulator, the exact location of which I cannot find as it is between the rail and regulator when the gun is put together (the source has to either the twin holes labled "-oil-" or the On-Off best as I can tell). The leak disapears immediately after the marker is discharged and then slowly gains intensity again. This maybe entirely unrelated to the real problem however.
Has any body experienced any problems like this? What is going on, what could be doing this to my mag? I don't want to have to send my mag back, but unless I can fix it I'll have to. Can any one help me?

[kenny45749]

There is alot going on in your explanation, but I will address what I can. You having to whack the back of the gun sounds like the bolt is sticking. Have you tried using different size spacers in the power tube? I had very similar issues with my minimag years ago, before i got spacers for the power tube. As far as the leak that you hear between your valve and the rail, I would say check the o-ring that is actually on the outside of the on/off cylinder that you first see when you begin pulling it out of the valve. For now thats all I have. I will think on it some more, but hopefully someone will get you an answer if I dont. Hope that helped, good luck.

[athomas]

If you are getting shot inconsistencies and have a leak somewhere in the middle of the valve, I would check the regulator assembly. Take the velocity adjustor out and clean the reg assembly, maybe change some o-rings. Replace any damaged or dirty o-rings. The leak is probably caused by the o-ring around the outside of the reg piston assembly. Dirt will cause inconsistecies and even failure to recharge. I saw a piece of sand in the reg cause this same effect.

[BlueTies]

just a question did these things start happening after you got your double trigger ? i think that i heard something bout new parts changig tings which could be fixed by changing the powertube spacer but i dont know

[mountainbob84]

the double trigger was on the gun when I bought it. the grip frame is stock, it has just had the trigger guard cut out to accomodate the larger trigger.

[tombraider68]

You should definitely try what Athomas and Kenny45749 suggested. Since you purchased it used there's a chance that the previous owner never cleaned it or replaced any orings. I too would suggest replacing all the orings and the seat. And find the right spacer to stop the bolt from sticking.

[athomas]

I forgot to address the sticking issue before.

Part of your problem may stem from bolt stick, which may be caused by a worn bolt spring, or a powertube spacer that is too short. The easiest to fix is the bolt spring. Check the length. When on the bolt it should extend past the tip. If the spring is ok, then try a longer powertube spacer.

The symptoms of bolt stick are that the gun will cough after a few shots. The velocity may fluctuate because the front chamber doesn't recharge properly. When the bolt sticks, the trigger rod won't be pushed forward so you won't feel any pressure on the trigger either.