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G3: Leak Down Barrel

If your marker has an air leak down the barrel. Check the items below. ​Reference the manual as needed. 

Issue:
Bolt Position Test:
  • With your marker off and degassed (no air source attached), move the bolt to the forward position then air it up.  If this doesn't fix the issue, move on the next step.

  • The leak down the barrel may be from the marker body o-rings, located in the front and rear of the feedneck. With the marker off but aired up, place your finger through the feedneck and place it over the face of the bolt, which should seal the face of the bolt. If you can feel air pressure building up behind your finger, try changing the small back cap (stem) o-ring. If pressure does not build up and you feel air around the outside of the bolt, try changing the breach/body o-rings. 

    • #11 - Small Back Cap o-ring: 13mm ID x 2mm CS

    • #3 - Internal Body o-rings: 17.17mm ID x 1.78 CS (x2)

    • #4 - Bolt Sail/Body o-ring: 19mm x 2mm

Bolt Pressure Test:
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  • Remove the back cap and bolt and wipe them down to remove any lube or debris. Next, inspect the o-rings within the body for any visible damage and replace if needed. Before reinstalling, lube the o-rings with a small amount of Dow33. 

    • #12 - Large Back Cap o-ring: 21.95mm ID x 1.78mm CS (x2)

    • #11 - Small Back Cap o-ring: 13mm ID x 2mm CS

    • #3 - Internal Body o-rings: 17.17mm ID x 1.78 CS (x2)

    • #4 - Bolt Sail/Body o-ring: 19mm ID x 2mm CS

Bolt & Body O-Rings:
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