'The main cause of this is liquid CO2 getting into the gun; for example, by firing the gun while pointing it down at the ground. Even an antisiphon tank cannot help you here (that's why I went with an expansion chamber and remote) - don't fire the gun where the front of the tank is below the back end of the tank. You can clear this up in the field usually. Turn the powerfeed off to stop ball flow and fire the chambered ball into the ground. (Make sure people around you know what you are doing and are wearing masks). Now you should have no balls feeding. Point the gun up into the air and fire off a couple of shots of gas; this should clear out the liquid and solve the problem.'

'I discovered this problem after a mishap happened at our local indoor field. The guy filling the tanks droped my 12oz and bent the threads on it. He gave me a new tank, which didn't have an antisiphon on it (I was running bottles right through the back CA adapter then). I went out and my guess is a lot of liquid got into the regulator or some debris. I think the regulator overpressurized and blew a small leak into the place where the pressure gauge screws into the regulator block (mine was near the top). I found this leak because I noticed a hissing sound coming from the gun as I had stripped and cleaned and oiled it at home. I covered the back end with soapy water and saw the bubbles forming at the guilty location. The regulator was replaced by Indian Springs, possibly the pressure gauge too. The problem is now solved; the Desert Fox is a tight ship.'

"Congrats on your Fox! the bolt should be lubed where it sets on the reg and where the bolt spring rides. also, put a few drops in the ca adaptor to run through the reg itself. ICD recommends changing out your bolt spring every few cases, however I replace mine about two or three times a year, and I put quite a few cases through it during the tourney season. good luck :) Spring"
springdog@hotmail.com in the ICD Discussion List

'The symptoms of this are an full-auto type of effect when shooting - 2 or more rounds are fired in rapid succession after a single trigger pull. This problem can be caused by liquid CO2 entering the gun (this liquid problem is usually the cause of many of the gun's malfunctions) but can also be caused by a problem with the regulator.
 
I had a slight regulator leak and the constant escape of gas was rapidly cooling the back of my gun. If I fired a rapid barrage, my regulator would cool down so much I might start sucking liquid and that caused a bolt jam usually. This happened in a speedball game and was bad. I was able to fire shots at a slow rate, popping a couple off and waiting a couple of seconds, then firing again - thus allowing the back to warm up a bit. This allowed me to cover the back of a building and prevent a run on that wire but prevented me from moving up in support.
 
If you have liquid entering the gun, you need to prevent this, antisiphon works somewhat but I prefer an expansion chamber. I had the verticle bottle adapter attached by Indian Creek for that purpose and put a Bob Long Expansion Chamber on it with a bottom line.'

'There can be several causes for this problem. The symptom is that the bolt doesn't cycle completely, coming to rest beyond the sear and partially obstructing the powerfeed. I've had balls even partly pinched between the feed intake and the bolt putting a dent in them. If this happens you are really PUCKED if the game is on - FIND A SAFE SPOT TO HIDE to work on the gun. You may have gunk in the gun obstructing the bolt travel or you could have insufficient pressure when firing which doesn't compress the main spring enough allow the reset of the bolt. You may even have a small double fire where the bolt fires, cycles and an automatic second pop pushes the bolt forward past the sear again - but not cycling completely.
 
First, clearing the gun. You probably have a ball chambered and may have a pinched ball, plus the barrel is preventing further feed. With all of those balls in the way, it can be difficult. You need to push the bolt back behind the sear with your finger or squeegie or some other long object. Remove the barrel and get any ball that is chambered out, push the bolt back and clear any pinched balls. If you have a pinched ball, you probably cannot turn the powerfeed off, so it is probably best to remove the hopper by turning the gun upside-down and shaking the balls down the elbow into the hopper - pull it off and set it aside (upside down- so the balls don't roll out). Once all the balls are out, see if you can see paint or other crud in the upper receiver. If it is there clean it out - if you have a squeegee and some alcohol in the field - super for you. Point the gun in a safe direction and pop off a single shot. Does the gun cycle properly? If it double fires and this is leaving the bolt forward see that section of this document. If its still sticking, strip and clean and oil the entire upper internals.. if that doesn't do it, call Indian Creek.'

Tom Smailus: 'I had this happen while playing and after cleaning the gun. This can be caused by the regulator 0-rings being damaged or by debris or dirt being on the regulator o-rings as well as a leak in the regulator, for example out through the pressure gauge threading. The leak of air prevents the regulator from properly shutting off the intake and the pressure just builds up: you fire a shot with much more than the 400-420psi of CO2. You can notice this buildup on the pressure gauge. I sat and watched how after a test shot the gauge went from 400-430-450-500-520.... Another cause if this is dirt on the regulator internals from dirty CO2 - especially if you have the old, double ball-bearing regulator.
 
This type of problem must be corrected. First check the o-rings on the regulator to insure they are not damaged (Dissassembly of Fox) and that there is no dirt from the gas supply inside the regulator or on the o-rings. Obviously, replace any worn or broken o-rings. Clean out the regulator with a cotton swab and some rubbing alcohol; lightly oil the o-rings to remove dirt from them. If the problem persists, assemble the gun, pressurize it and cover the back end of it, paying attention to get all seams, with soapy water (cold water and some liquid dish washing detergent works well). Bubbles will form where ever there is a leak. If you see a leak - check the o-rings and tightness of the connection at those places. If you cannot fix it - give Indian Creek a call.
 
If you have the old regulator design without the cup seal which has the ball bearing in the regulator valve instead, you will be prone to have this problem from dirt collecting on this ball-bearing. Call Indian Creek Design and send the gun in to have the new internals installed with the cup seal.'

Tom Smailus: 'This was a symptom I was having when I initially got my Desert Fox. I would go out and play and suddenly start breaking balls left and right. It took me a while until I realized that my grabbing the barrel, or just the vibration of firing and/or running was loosening up the barrel from the upper receiver. Once this happens, there is a small gap where the paintball can catch on the inside of the ball travel from receiver to barrel. I verified this at the test stand by shooting a couple, loosening the barrel a very small amount and shooting again - shred.
 
Initially, I tried all sorts of normal remedies: thightening it very tight by hand, teflon plumbers tape, electrical tape on the outside; basically everything short of putting Loctite on the threads (DON'T DO THAT!). I called up Indian Creek and they had me send the gun in. I got it back with a new upper receiver - the barrel now tightened down much better by hand than before. Apparently there was some machining problem in the manufacture of the upper and/or barrel and upper matching. It took very little force to start unscrewing the old barrel/upper combo - now it is MUCH better.
 
If you are breaking balls while playing, as soon as you notice this, give the barrel a tightening twist. If it moves when you tighten it - then it is loose. The barrel needs to stay in the fully screwed on position when in use; try the plumbers tape or give Indian Creek a call about it if the problem persists.'

Bror Jace' Barrel and Paint Guide

Miscreant's Article on Barrels and Paintball sizing