Benjamin AS 392 seal missing

[JoninMA]

I have a LNIB Benjamin AS 392. The only thing wrong with it is it's missing the seal where the Air Source cartridge/12g cartridge adapter threads into the rifle. I've tried a couple of O-rings, but they aren't a good fit and the gun leaks down so quick I can only get 1 or 2 shots off when I use the 12g adapter. Is there a proprietary seal, or has anyone had luck with flat style orings/ rubber washers?

[Zsigmund]

 Hey Jon,

 I recently re-sealed one of these using a kit I found on Ebay. I may have a spare of that o-ring, if so I'll measure it when I get home from work.

 BTW, I had one type of single Co2 adapter that would not work with my rifle, it would leak out no matter what I did.

 Best Regards,
               G

[Zsigmund]

 My chinese digital calipers say that o-ring is a #113.

 I've got a few #113 rings in urethane. PM me and I will mail you a couple to try.

 Best Regards,
                G

[JoninMA]

Thanks, I picked a couple up at the hardware store and I'll give them a try. If they don't work I'll shoot you an email.

Jon

[Zsigmund]

Thanks, I picked a couple up at the hardware store and I'll give them a try. If they don't work I'll shoot you an email.

Jon

 Very good, best of luck! FYI I've had seal (750-013 O-RING, PRESSURIZER) fail twice on my rifle over the years. It would cause a similar leak down symptom.
I've attached the AS392T EVP for reference.