Flawed Systema 2012 Stainless Cylinders

[mcguyver]

As some have found out the hard way, and others have heard, there has been a new problem introduced to the PTW world with the 2012 guns. In some of the stainless cylinders (regardless of velocity), the rack gear wears down very quickly, sometimes causing wear on the sector gear. This is a result of too much play in the piston as it moves in the guides.

The stainless cylinder is basically a stainless tube and the piston guides are in an aluminum insert that is glued into the stainless tube. It is the insert that is over-spec, and it is not repairable.

Tonight I managed to finish a prototype rebuild of a flawed cylinder. I managed to harvest the piston, but the rack gear needed to be replaced. I took an old M130 cylinder from about 2008 that was swelled beyond repair, it had been sanded to try to make it fit, but to no avail. A teammate is a machinist, so I asked him to turn down the old cylinder so that the guide portion would fit inside the stainless shell. The older shells were machined correctly, so I know the guides will keep the piston true. After assembly with an M130 spring, I get a nice and stable 398 fps (Orga loss of 20-30 fps) in my gun and 425 in another test gun.

My biggest concern is ensuring the new insert stays stable and glued to the stainless shell. So far, 100 test rounds are fine, but that is not enough. I am going give it 5-6000 in a couple weeks at Battlefield, and if it is going to fail, I want it to fail there.

I posted a want add for dead cylinders as I want to try a few more if these. If someone wants to contribute to PTW engineering and perhaps have their cylinders functional again (no guarantees, but if you have a dead one now you'd be no further ahead if it didn't work anyway), shoot me a PM.

[mcguyver]

This is the finished prototype. Ready for testing.

[mcguyver]

The OEM insert from the stainless cylinder

[mcguyver]

The old cylinder to be harvested

[ThunderCactus]

Just to note, if red loctite doesn't hold that bitch in place until it dies, you could always (and very easily) pin the sleeve in two places
Should be enough meat on the aluminum side and strength on the stainless shell to hold it securely

[DipTwit]

How easy is it to test for this 'play' in the piston's movement - are we talking mm or microscopic play? Just wondering how ppl can avoid it before the fact...

[mcguyver]

Originally Posted by DipTwit

How easy is it to test for this 'play' in the piston's movement - are we talking mm or microscopic play? Just wondering how ppl can avoid it before the fact...

If you have a flatblade screwdriver, push on the rack gear straight on to the rack. If the piston moves up or down, it is flawed. It would move a couple of MM if you have a bad one.

Unfortunately, there is nothing to avoid if you have a bad one. Failure is quick and inevitable. There is no fix, except for recent prototyping, replacing the rack gear means you will get another 1-2000 rounds out of it before it dies again. But you may lose the sector gear as well. I currently have 4 rack gears and sector gears in the shitbox.

If you have a Velocity piston, you may be able to substitute it for for the Systema one, as some of them are oversized and fit those piston guides better. But just the piston, use a Systema rack, head and orings, the Velocity ones are not Systema spec and of poor materials.