Wednesday, October 6, 2010

Gamo PT 80 CO2 Cartridge Seal

I really didn’t know what I was dealing with…


Levering out the brass ring (I used a small screwdriver in the slots) so I could get a better look in the cavity for the seal. Notice the pot metal fracturing. I had to use gravers to remove the excess metal trapping the ring. In hindsight I suppose I could have left the ring in place.


Although with the ring removed I was able to measure for the diameter of the seal. The ring got beat up in the process. I wonder if Gamo just swaps the whole valve assembly when they service the pistols?


Drilling the seal hole.


Turning down to diameter.


Cutoff. The first one I made was about .05” thick, later I made another than was about .04” which worked better. The seal is basically just a flat disk.


Seal in place.


Brass ring pushed in. In theory it should stay put.


Testing the assembly with a used (empty) cartridge. Reassembly of the pistol was in the reverse order of disassembly. I managed to flip the “teflon” exhaust seal around and at first the pistol wouldn’t function, I disassembled the pistol several times and finally realized that I had it flipped. It now functions normally and holds gas. Once I get some clips I’ll test it out and see if there are any other problems.


CO2 cartridges said...

Good try Nick! I'm trying to do this too. Thanks for the information :)

Jason said...

What material did you make the new ring out of, and what was the OD/ID dimensions?


Nick Carter said...

90 or 95 durometer urethane rubber.

Nick Carter said...

Didn't write down the dimensions at the time, just make to suit.