Quick explanation of the power tube spacers

[DamianTC]

If it is freezing, yes. Compressed air gets cool when you drop the pressure on it, but not enough to freeze. What kind of trigger do you have and how fast (and long) are you shooting?

I have a classic automag with a level 7 bolt, it happens when I start shooting rapidly for 10-20 shots in like 3 seconds

I plan on getting an Xvalve w/ level 10 soon. does that bolt still use the same method of power tube spacers?

[Spider-TW]

I have a classic automag with a level 7 bolt, it happens when I start shooting rapidly for 10-20 shots in like 3 seconds

I plan on getting an Xvalve w/ level 10 soon. does that bolt still use the same method of power tube spacers?

The level 10 has its own kind of power tube oring "carriers". There's lots of info in the Level 10 stickies, but in short, because the L10 is so soft and friction is so critical on that seal that the carriers allow you to adjust two things independently. The carriers hold the outside of the oring and squeeze it to adjust the friction on the power tube stem. A "smaller" carrier squeezes the oring tighter than a "larger" carrier.

The other adjustment is a lot like the power tube spacers. Instead of different length carriers, they are all the same length and you add shims to push the oring down the tube farther. However, instead of adjusting the seal/no seal like the level 7, you're adjusting the point at which the level 10 can vent. If the level 10 moves forward and doesn't vent, it can get stuck on a ball. If there are too many shims pushing the oring beyond the reach of the level 10 stem, it will vent all the time. Valve pressure makes sure that any slack space left in that area is all at the back of the power tube and the carrier gets pushed as far forward as the carrier and shims (if any) will allow.

So when the instructions and athomas say adjust your carrier size first and add your shims second, they mean it because the sequence is just as important as the actual choices of carriers and shims so that you can tell what is happening when you get a leak in the process.

What's really bad is when someone tries to fix a mag by changing power tube orings, carriers, L10 shims AND ULT on/off shims randomly. :spit_take

[georgeyew]

Wow, that makes perfect sense now. I can picture it in my head. Thanks for the detailed explanation.

[Spider-TW]

I always thought that a longer spacer will squish the oring more which is why if you have barrel leak you use a long one, your trying to create more of a seal. A shorter spacer obviously allows the oring to retain more of its original un-squished state.

The bolt stem in the level 7 must normally sit on top of the oring, not really through it like the level 10. When the stem goes through it and gets pinched with the oring is when you get bolt stick (spacer too short). So you're trying to position the oring where the bolt will come to rest on top of it enough to seal.

Damian, have you tried a fresh oring with the 220 spacer? O-rings get old and hard and 5 mils may be too much for a brittle oring to cover.

[DamianTC]

Yes, I tried a 220 and new o-ring and the bolt did not stick, but when I would start to pull the trigger, the power tube would start to leak before the gun fired. This is happening after I would shoot rapidly. I was wondering if this was caused by frozen CO2 becaue I would notice after rapid firing, the tank is frosted and the regulator was ice cold aswell. That is why I was thinking a compressed air setup might be the solution

[Spider-TW]

Yes, I tried a 220 and new o-ring and the bolt did not stick, but when I would start to pull the trigger, the power tube would start to leak before the gun fired. This is happening after I would shoot rapidly. I was wondering if this was caused by frozen CO2 becaue I would notice after rapid firing, the tank is frosted and the regulator was ice cold aswell. That is why I was thinking a compressed air setup might be the solution

Yeah, HPA is about the only way to sustain rapid fire.