KJW Hi-capa magazine lip replacement problem
 

hey all,
I replaced a broken magazine lip on a KJW magazine, but since then it doesn't cycle properly, like there is not enough power output.
It does the same thing with two different replacements parts.

since it's the same with both parts I'd figure the problem comes from the mag's shell, but there's nothing I can see...

I tried sanding a little on top of the lip where it touches the nozzle, I thought it was rubbing against the nozzle at blowback time, but apparently it's not that.

any ideas?
thanks a lot!

Did you just recently take your blow back unit out of your slide? Check to see if you can't reseat it...it may be a bit cockeyed and tilting down, pushing on the mag too much and causing drag.

Loosen off the hex screw that holds it in (where the hammer would strike the firing pin of a real pistol)..and if there's a screw that goes in the top of the rear sight, take that out (to test).

Not fall out loose...just ease the torque off and barely finger tight.

test fire like that. If it's much better, then your blow back unit alingment is off. Torquing down on that rear hex screw can often pull the BBU off.

I read in another thread that you removed the screw in your blowback unit holding in your floating valve and spring while you were trying to remove the rear sight.

That's your problem.

ok, what happened when I removed the screw?

I put it back in before testing though...
and also the other magazines work perfectly...

oh ok, makes sense.I'll try that.

thank you folks!

Worn down mag-catch?

fixed: output valve sitting too low (screwed in too tight )
unscrewed a little bit: works.

this would probably also work by adding a little material to the valve's push-button.