i picked up a spyder clone years ago at a yard sale. I gassed it up and big whoosh down the barrel. Owner told me it just needed an oring.....
took it home, dissasembled, checked all the orings and sealing faces, reassembled exactly as it was. tried it again with the same result.
Waaaaaait a minute! Why the hell was the poppet inserted from the hammer side????? yeah thats not right lol.
I swapped it into the valve side and everything was good to go. Keep in mind that I hadn't taken apart a blowback in 10 years and was having a brainfart when I reassembled it. Felt silly afterwards.