Reply To: FX 400 Breech Probe Seal

Forums PCP Airguns FX 400 Breech Probe Seal Reply To: FX 400 Breech Probe Seal



Cahil, I had mine blow out the other day. It ended up on my shooting bench. I’m pretty sure I was using my magazine at the time so when it blew it probably rolled back on the pellet probe until I cycled it and then I think it fell out on my bench. The breech seal seems to be a problem with the 400’s. Get some 009 70 durometer for spares until you can get some factory O-rings. Had you noticed the gun getting louder at the breech on previous shots? The wooden dowel rod inserted down the barrel and used as a back up to keep the O-ring from working it’s way past the barrel groove is the best bet. If you don’t have the dowel rod it can be a real pain to put back in. No need to remove the barrel. Use something like a broken tooth pick or something small and plastic to help maneuver the O-ring into the groove while keeping it in place with the dowel. As mr.grimm stated 3/16 is the correct size dowel rod.