oerllikon, on Nov 9 2008, 10:37 PM, said:
Is there a such thing as an "Air Hammer" (Like a water hammer) could it be the air hitting the ball suddenly?
Or is it a weak wall on paint?
That is a close guess to what I think may be happening. Weak paint is the overall problem, but a solution I'd try is this: Turn down the input pressure and increase the velocity knob. This is like increasing the dwell, so the valve is open longer but delivering less pressure over more time. With high pressure input you have the valve open for a brief time (turning down the velocity screw) ((Assuming you have a cocker style system for a pump) This will put less stress on the weaker paintballs as they are propelled down the barrel. If the valve is open too long (velocity screw up to high) you may get blowback with a semi auto, but this situation is a pump, so you probably won't open the breach before the valve closes again.
Also the bolt slaming into the ball could start the process of structural failure on the paintball when it comes forward to load, again more for a cocker, where you would want the LPR turned down as much as possible to just cycle the bolt and cock the hammer, but with a pump if you got a little carried away slaming it forward, you may apply to much force to the ball all at once.