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AirGunEric · Site Admin

Well, I go outside and see the groundhog that's been eating my wife's flower bulbs and just generally annoying me by digging around/underneath the flowerbed walls I built a few weeks ago (leaving a giant pile of dirt laying about).

So, I go into the house before the thing can get away and open the gun closet. Ooops- only two guns in there- a 1077 and a Quest. Quest I was monkeying with the other day and haven't re-sighted yet- so it will have to be the 1077. Sure, the 1077 may not afford a terribly "clean" kill at anything but a short distance- but its got 12 shots right there in order to plant in quick succession and bring the groundhog down.

So, I turn the newly-installed (before I put it away the last time) AirSource bottle flow control knob- and a small amount of Co2 starts leaking- so I turn the knob off and screw the bottle in a bit tighter. Turn the knob back out- no leaking Co2- aim, fire- nothing.

AirSource bottle is empty! I never took a shot with it and it was full when I attached it. Groundhog has long since heard me and run back underground- so I investigate the rifle. A $10.00 AS bottle wasted- it obviously leaked out while the gun was sitting.

Now, here the 'meat' of it for Crosman AirSource owners:

Turns out the "bottle seal" which seals the very top of the AS bottle around the piercing pin has basically disintegrated. Fortunately, I have a brand-new, never used AS adapter laying around to compare it with. The seal is too thick to allow the AS bottle to fully meet the piercing pin without it being compressed significantly. It is this compression along with the rotation of the bottle to attach it to the adapter that chewed up the seal.

Crosman doesn't list a part number for this seal- but Chambers in the UK does- and even sells them in a "10 pack". Obviously, these things go bad frequently. The AS adapter in which this seal was installed had six AirSource bottles attached to it before the seal disintegrated.

So, for anyone thinking of using a Crosman AS adapter- be sure to check that seal at every bottle change, maybe lube it each time, and keep a supply of extra seals on hand for when it does disintegrate.

I'll post up the Crosman part number for the seal and pricing tomorrow once I've had a chance to call them. Personally, I think after only 6 AS bottles, one of which was completely wasted- they should maybe send me a seal as a warranty gesture...

23ib0d0n · Moderator

That adapter failed on me last year.

After rebuilding the stupid adapter, I've been using metal polish and 0000 steel wool to clean up the airsource threads.

Then, I generously lubricate the threads with silicone grease before putting it in the adapter and haven't had that problem anymore.

~
Of course, it does feel alot like a pound of prevention is worth a half pound of cure in this case, but I don't worry as much about losing an entire airsource charge again . . .

AirGunEric · Site Admin

Well, no update on this seal so far- apparently when I called Crosman at around 4:00 yesterday, their computers were acting up and they couldn't tell me if the seal is available, and if so, what the price would be.

Chambers Gunmakers in the UK sells these seals, but under their own part number. They sell singles (their part # OR075) and packs of 10 (#OR075/10) so obviously this must be a very common problem.

When I get my new digital camera- I will post a picture of what the difference is between the ruined seal and a new seal. In the meantime- I may see if a plumbing washer 2-3mm thick will work.

Perhaps this seal disintegration is common on other guns using the AS Co2 cartridges- Boeing299 has had problems with his Umarex AirMagnum 850 which uses an 88g AS cartridge and has a rubber seal as well.

AirGunEric · Site Admin

Partial Update- the bottle/adapter seal is Crosman Part # DMC4TA-006, and costs about $1.50. I have a couple on order but they have not yet arrived.

dbarr · Member

I'm not familiar with how the AirSource screws into the 1077, but with the 850 Airmagnum, there is an o-ring that seals around the outside of the AirSource's smooth section (before the threads). I was able to find a replacement o-ring at the local hardware store.

A tip from B.B. Pelletier (Pyramyd Air blog - http://www.pyramydair.com/blog/) is to put a couple of drops of pellgunoil on the tip of an AirSource bottle before installing it. That keeps all the seals/o-rings in the airflow path conditioned. (Same with powerlets.)

DB

AirGunEric · Site Admin

Now that I've got the new camera- here's the info and pics.

First, the new o-ring deal came from Crosman using part # DMC4TA-006

It has an OD of 18mm (23/32") and an ID of 12mm (15/32")- and a thickness of 3mm (1/8"). Both it and the old seal are fairly rigid. I don't know their durometer rating- but they are much harder than I had expected.

Here's the old seal still in the AS adapter:

and again, the other way around:

The broken seal out:

And the new seal installed (put some Crosman Pellgunoil on it first):

Now here's something interesting. Another AS adapter I had has a totally different seal in it for the bottle. It is a compression seal that the bottle tip butts against:

I've never used this specific AS adapter- so I can't say how well the seal holds up compared to the o-ring version.