I just got my PCS saw stock for my a-5 off e-bay. When I went to install the stock, I noticed that the piece that goes into the gun is a solid plactic piece. I was wondering if it would be a problem, such as have air leaks, since the original piece has an o-ring on it?

Mine (Tapco SAW stock) does not have an O-ring and works just fine. The rear section of the marker is never pressurized beyond the o-ring on the rear bolt (unless the o-ring fails, after which air coming out your stock would be the least of your problems).

Here is a diagram showing that air never gets back that far under ideal conditions.

Thanks a lot for the info.
Good, I was worried I bought something very cheaply made. Other than that, I really like the stock. Has a good solid feeling. What is the maintenance schedule for the internal o-ring, change every year if used moderately?

I oil all the o-rings in my marker following every day of play after I clean it. I would replace all the o-rings annually and on an individual basis as wear develops. It also never hurts to carry a spare kit in your gear bag just in case.

love th diagram

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