As with any Tippmann and in fact any paintball gun, make sure the marker is properly cleaned and oiled. This solves many problems. Having said that, when a marker won’t stay cocked the first things to look at are the sear, bolt, and bolt oring.
The sear and bolt connect together to hold the bolt in the back position. If one of these is damaged or worn then they won’t connect correctly and the bolt can free cycle back and forth. If you have to replace one then you should probably replace the other at the same time.
The bolt / hammer oring is what seals between the bolt and the body of the gun. You need a good seal here so the excess air from the firing sequence can blow back the bolt to the back position to catch on the sear. If that oring is worn, broken, missing, etc then the air will escape around it and not give sufficient force to get the bolt back. If the oring is dry or swollen then it might be creating too much drag to allow the bolt to freely move back far enough.
So, rapid fire / won’t stay cocked: Check your rear bolt, sear, and rear bolt oring.
STILL having a problem? Check your velocity. On the first shot, do you get a good normal velocity shot off or is it low? If your gun is rapid firing AND your velocity on that first shot is low then you could have a cracked power tube. A cracked tube is similar to a bad rear bolt oring in that the air is escaping around to the wrong place rather than forcing the bolt back. A cracked tube will also cause low velocity as air going forward also escapes out the crack.
Symptom: rapid fire
1. Clean / Oil – check
2. Examine rear bolt and sear and power tube. Replace worn or cracked items and replace the rear bolt oring.
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