My Minimag came from PBgear.com....

[krafty]

When you screw in, then unscrew the tank, are there any cuts, nicks, or slices in the o-ring on the tank? If so, check the threads in the ASA for burrs or uneven spots. If not, make sure you're using tank o-rings that are thick enough to seal in the ASA. Put a drop of oil on your finger, and oil the o-ring to make sure it's sealing properly. Also make sure you're screwing the tank all the way in.

Are you tipping the gun downwards when you're screwing in the tank? It almost sounds like you may be freezing the o-ring as you screw in the tank, causing it to leak.

[FordPrefect]

Krafty, no, the o-ring seems to be fine when I screw it back out.

I think that it might be the tank now, because it has a couple dents on the top, and the could be it. Maybe..

[Blazingace]

If the dents are just above the o-ring in the seating surface that might do it. I had a screwy tank with a dent above the o-ring and I had to be very careful when I screwed it in. I had to screw it all the way in and then unscrew it half a turn. I was using it on a VM-68 but the adaptors are the same thing. Try your friends tank out, with the extra o-ring if you have to. I really think it might be your tank now also. You can usually get a new valve on the tank for like 8 bucks. So try a new tank or valve.

[krafty]

If nothing else, I've got an extra ASA or 2 lying around. If the tank thing doesn't work, maybe I can send you one to try.

[than205]

I was thinking it was your bottle. (I have a similar problem with my old 20 oz) What's been suggested to is to not only have fresh oiled o-ring on the bottle but also to put an o-ring all the way up inside the ASA. My teammates have done this in the past with success.

[Polishpickles451]

I ordered a minimag from PBgear about 5 months ago and they sent my a 68 powerfeed Classic with the RT stock barrel. Works great, so i'm happy, but be very careful about ordering from PBgear.com.