XMag's first shot....chuf!!!!

[Hellaspaint]

We have an XMag. If it is gassed and seat for a while the first shot is with a chufffff ( no paintball is coming out the barrel), the bolt reset and then start shoting normally!!!!!

What can cause that? Spring, shims (we have 2), carrier, a very small leak??????

Any suggestions?????

[athomas]

You are getting bolt stick. Usually, a larger carrier fixes that. A tiny leak is most likely too many shims (based on the fact you are getting bolt stick and a leak).

[Hellaspaint]

Thank you Athomas

so, the idea is that a small leak because of shim, or, and, very tight carrier is decreasing the pressure behind the bolt and if the gun is seating for a while there is not enough pressure to fire the paintball, because after the first shot-chuffffff is shooting normally.

sorry of my poor english!!
Thank you any way.

[athomas]

The bolt sticks when the force required to move the bolt is greater than the chamber pressure can exert on the bolt stem. If the carrier is too tight and sits for a bit, the carrier o-ring sticks to the bolt stem. This increases the amount of force required to cycle the bolt and quite often it won't fire at all because there is insufficient pressure acting on the bolt stem. Once it does fire, the carrier o-ring is broken free and the gun will cycle freely because the only force acting against the chamber pressure is the force of the bolt spring.

Usually if you are getting bolt stick, it means there is a very good seal between the carrier o-ring and the bolt stem. Therefore, the only place the bolt can leak, is out the vent hole and it can only do that if the vent hole is exposed due to carrier/bolt positioning. By removing a shim or two, you allow the carrier o-ring to move farther up the bolt stem away from the vent hole. This means the vent hole will not leak while the bolt is at rest and will only vent when the bolt moves forward and then stops during firing allowing the vent hole to be exposed past the carrier o-ring.

[Hellaspaint]

Ok, i understand very well!!!
Thank you for your time.