Airsoft Canada - View Single Post - Tanio Koba / KJW M4 GBBR Basic Information and FAQ

Fab · July 15th, 2011, 08:53

Hi,

I just got my brand new KJ M4 3 weeks ago (my firts GBBR but I'm used of assembling/modifying AEGs), after reading many forums, I installed the usual recommended by experienced GBBR users

Craddle velocity reducer
Cradle Piston
RA_Tech 6.01 380mm tightborre

I saw the video on youtube for installing the Cradle velocity reducer, everything went smoothly but after passing the M4 on the chrony I'm really disapointed...the fps are totally inconsistent !

with 1 small spacer + the o-ring, on the .25 (chrony set for 0.25g BBs ) it ranges from 325 to 420 with sometimes a few shots around 390fps but still really really inconsistent....same thing with 0.20g

I checked the velocity reducer many times, changed the spacers, checked that nothing was loose, well lubricated (not too much), cleaned the hop-up but still the same thing...after firing around 20~30 mags I'm really disapointed....any suggestion of what I did wrong ?

July 15th, 2011, 08:53	#503
Fab Trader rating Join Date: Jun 2003 Location: Montreal, QUEBEC	Hi, I just got my brand new KJ M4 3 weeks ago (my firts GBBR but I'm used of assembling/modifying AEGs), after reading many forums, I installed the usual recommended by experienced GBBR users Craddle velocity reducer Cradle Piston RA_Tech 6.01 380mm tightborre I saw the video on youtube for installing the Cradle velocity reducer, everything went smoothly but after passing the M4 on the chrony I'm really disapointed...the fps are totally inconsistent ! with 1 small spacer + the o-ring, on the .25 (chrony set for 0.25g BBs ) it ranges from 325 to 420 with sometimes a few shots around 390fps but still really really inconsistent....same thing with 0.20g I checked the velocity reducer many times, changed the spacers, checked that nothing was loose, well lubricated (not too much), cleaned the hop-up but still the same thing...after firing around 20~30 mags I'm really disapointed....any suggestion of what I did wrong ? Last edited by Fab; July 15th, 2011 at 09:04..