KJW KP-08 mags emptying after 1-3 shots

[Varjeal]

Greetings.

Recently I purchased a new KJW KP-08 as well as a used one (both the CO2 versions).
4 of the mags are propane, 3 are CO2.

Here's my problem (same issue with both guns):

All the mags empty after one-three shots each with the slide locking back. None of the mags leak on their own, so I'm guessing something is wrong with the pistol(s). If someone can provide a trail of if/then's to follow that would be greatly appreciated.

So far I've tried the following:

1. Field stripped, cleaned as many of the parts of guns as I could comfortably get at.
2. Disassembled and lubricated the mags.

Also, if there is an experienced gas gun tech in Alberta willing to look at these for me feel free to pm me as I'd consider that option as well.

Thanks.

[Styrak]

If they're new why don't you talk to or take them back to the store you bought them from?

[Varjeal]

Only one is newish. Warranty of course is over and the store is a bit far to drive to, hence the query.

[Styrak]

So you're saying the slide locks back, and the gas vents? That doesn't make much sense.

[Varjeal]

Hmmm...well...maybe I'm not understanding exactly whats happening as it occurs rather quickly. Perhaps the gas is expelling mid-cycle as the slide locks back. Regardless, neither of the guns function properly and I need them fixed.

[Kos-Mos]

Please explain how it locks back.
Does it lock on the slide lock? (almost as back as it ca go)?
Or does it lock on the hammer, returning to battery?
Or is it midway between?
If the nozzle moving freely? Does it stick or jam when returning to battery?

[Styrak]

Do you have someone to send it to? If not, I could take a look. It could be many things and internet troubleshooting is sometimes very difficult.

[Varjeal]

Ok..just a bit of an update for those having perhaps similar issues. I had a friend who's more familiar with gas gun internals than I have a look, and he found something interesting which I wanted to report. Apparently ALL of the propane mags had leaky/sticky valves (these are original KJW mags btw, not knock-offs). Some teflon tape fixed the issue right up.

The CO2 ones still expel all gas though after 1-3 shots, and now I'm thinking it has something to do with the part where the canister punctures....perhaps not sitting square and flush to the canister...just a guess at this point though and I've no idea how to test that theory. Still looking for potential solutions if anyone can offer any. Perhaps in the off-season I'll put 'em in your hands Styrak for a look-see. Thanks for the offer.

[Styrak]

It's good you got the propane mags figured out. And I don't deal with CO2 mags, hate em and they're impossible to fix most of the time.