Look at what I discovered tonight.

Tonight I decided to do some night plinking with the .22 Marauder. It's nice and silent, and I wanted to give the JSB 15's another chance since I got my SSG going good. After firing one clip I start hearing air coming from somewhere. I figure maybe the valve might have gotten stuck, or an o-ring has given out somewhere in the gauge block. Came home and disassembled with O-rings on hand to do the quick fix, and eventually I open the valve itself to discover this.

 
that would be the valve stem I believe I seems the circle part in the middle snapped off under stress it should b near the head that makes the seal after the spring/pressure pushes it back ion place its really one of those things that can just happen pyramid air I believe is selling a replacement now a buddie of mine machined a custom one of them that's all metal with an oring grove I wanna try just haven't tore apart my m-rod to try it lol
​you could just fix or or take this as an opportunity to upgrade you system