Airsoft Canada - View Single Post - Sticky M9 blowback chamber on a KJW? Lack of hopup on it also?

ancorp · January 1st, 2009, 12:39

Bought a beater KJW M9 a while back, has always been having one small problem.The loading nozzle/blowback chamber/cylinder or whatever you'd like to call it - sticks forward at times. Taking it apart showed mangled blowback springs which I swapped out for new KA ones. Still the problem is there. Looks like there is too much friction between the rubber piston head and the cylinder. Tried AI silicone oil, helped a little but not that much. If I oil it and go to a CQB game, by the end it usually starts to lock the slide on some shots. But generally the force of the blowback snaps the loading nozzle into place. Sometimes it doesn't:

Perhaps a new piston head is in order?

Another issue - feels like there is no hopup present. I own 3 KJW M9s, and all 3 do this. They shoot at a good velocity (300fps+), hit hard, but the BBs drop fast. Even with .2g it doesn't fly straight at all, have to lob the BBs. (Don't see a hopup adjustment anywhere, I assume all mine have fixed hopup, their hop is set for .2s from factory). The rubbers look fine on all of them, one of the M9s looks almost brand new.

Any tips?
Thanks,
Alex

January 1st, 2009, 12:39	#1
ancorp AK Guru Trader rating Join Date: Mar 2005 Location: Vaughan, Ontario (near Toronto)	Sticky M9 blowback chamber on a KJW? Lack of hopup on it also? Bought a beater KJW M9 a while back, has always been having one small problem.The loading nozzle/blowback chamber/cylinder or whatever you'd like to call it - sticks forward at times. Taking it apart showed mangled blowback springs which I swapped out for new KA ones. Still the problem is there. Looks like there is too much friction between the rubber piston head and the cylinder. Tried AI silicone oil, helped a little but not that much. If I oil it and go to a CQB game, by the end it usually starts to lock the slide on some shots. But generally the force of the blowback snaps the loading nozzle into place. Sometimes it doesn't: Perhaps a new piston head is in order? Another issue - feels like there is no hopup present. I own 3 KJW M9s, and all 3 do this. They shoot at a good velocity (300fps+), hit hard, but the BBs drop fast. Even with .2g it doesn't fly straight at all, have to lob the BBs. (Don't see a hopup adjustment anywhere, I assume all mine have fixed hopup, their hop is set for .2s from factory). The rubbers look fine on all of them, one of the M9s looks almost brand new. Any tips? Thanks, Alex __________________