Old level 10 kit?

[factoid]

The sear should be ok. It takes a lot more than 8 cases to cause enough wear to be a problem.

The oring could have had a larger ridge around its inner surface. That would wear a bit more aggressively.

The carrier does not sit in exactly the same location each cycle. It does float in the powertube. The pressure in the chamber keeps it forward. The powertube tip keeps it at the correct distance. Any uneven surfaces on the oring could affect it. Have you tried a different powertube carrier oring?

When you invoke a leak, take the barrel off and put your finger on the front of the bolt and push it back and/or wiggle it around to see if it affects the leak. If pushing the bolt back stops the leak, then it could be an issue with the vent hole location/bolt position. If the leak changes pitch when you wiggle the bolt but still leaks when you push it back, it is probably just an oring issue.

Awesome tips, I will give those a try.

When you say carrier o-ring are you meaning the one that goes into the carrier, or the black one that wraps around the outside of the carrier?

I haven't swapped out either of them since I got it all tuned up.

[Ando]

The one that goes into the carrier

[factoid]

Wow this is a really bizzare leak.

I'll hold the trigger in and I'll hear a tiny hissing down the barrel. So I figure it's an on/off problem. But if keep holding it after a few seconds it stops.

Is there some residual pressure that stays in the powertube after the gun cycles and that's what's escaping?

I've checked my on/off and the o-rings are in great shape. I swapped with fresh ones just to be sure but it still happens. Like I said it stops after 5 seconds or so of holding the trigger and only with my longer spring. If I put the gold spring in it's fine.

Here's a couple pics I snapped of the sear. It looks pretty good to me. I can definitely see the bolt move forward a couple milimeters after I let go of the trigger and the sear catches it though. Not sure if that's normal or not.

[athomas]

What you are describing is quite normal. There is quite a bit of residual pressure left in the chamber after a shot. The amount of residual pressure is larger with a longer spring and is enough to exceed the surface tension of the oring-bolt stem contact area, but is not enough to seat the oring. The powertube carrier oring has such little pressure on the bolt stem that low pressures have a hard time seating the oring. This causes the tiny leak until the oring seats itself. The short sprig dumps more pressure so it is less of an issue. The oring is tight enough to hold back the reduced amount of pressure from the short spring.

Its hard to tell from those pics if the sear is worn. It usually takes 30 or 40 cases of paint to wear out a sear, so I suspect it is fine.

I would change the white powertube carrier oring and retune. See if it helps your situation with leakage.

[factoid]

What you are describing is quite normal. There is quite a bit of residual pressure left in the chamber after a shot. The amount of residual pressure is larger with a longer spring and is enough to exceed the surface tension of the oring-bolt stem contact area, but is not enough to seat the oring. The powertube carrier oring has such little pressure on the bolt stem that low pressures have a hard time seating the oring. This causes the tiny leak until the oring seats itself. The short sprig dumps more pressure so it is less of an issue. The oring is tight enough to hold back the reduced amount of pressure from the short spring.

Its hard to tell from those pics if the sear is worn. It usually takes 30 or 40 cases of paint to wear out a sear, so I suspect it is fine.

I would change the white powertube carrier oring and retune. See if it helps your situation with leakage.

Glad it's normal. I was worried something was defective.

I put in a new o-ring and switched back to the 1.5 carrier with the gold spring and one shim since this is the setup that I've not had any problems with. I wish I could get a longer spring working reliably, but I guess I shouldn't worry about it until I have problems chopping brittle paint.

[athomas]

If you have a new oring in there, try the longer spring. Take the shim out though.