SpudFiles

Thanks for the comments. OK...I checked a few areas and found 3 leaks....fixed those. I even opened the QEV to clean it out. The gun still leaks from the barrel. Actually, the gun will pressurize up to about 40 psi and when I disconnect the air hose, the gun completely discharges. I am filling from the pilot side and I believe I have the QEV orientation correct...or at least an orientation that lets me pressurize. Here is a pic to assist.

is it a male quick connect fitting or a tire valve?

wait.... your blowgun leaks becasue it's connected the other way round...

Indeed, the blowgun is made to receive pressure from the other side.
The gun fires on releasing the air hose? Thats a schrader valve you are using there right?
Well, on disconnecting, it leaks out air, simply pilotting the valve and BLAM.
Disconnect it really fast or use a check valve. Another method is to use a small balvalve inbetween and close it before disconnecting.

You're sure you tightened everything up with a wrench and used enough teflon tape (5 layers).

Thanks...I'll tweak it.

Switched the blow gun around...now I can get up 60 psi when I disconnect quickly. I still get a bit of hissing from the barrel, but I still have enough air to launch my nerf dart!