CTR-02 not locking back

[Mban2]

So I purchased a CTR-02 from a member on here.  The gun is absolutely flawless and a dream to shoot.  The bolt seems to have issues locking to the rear with both  Magpul mags and standard USGI aluminum mags.  I have fully adjusted the gas block and could not find a solution.   Could the aluminum bolt carrier be outrunning the speed of the mag follower?  And suggestions?

[davsco]

did it work before adjusting the gas block?  my ctr-02 been 100% perfect during the couple of years i've been doing 3 gun matches with it.  i'd just contact JP and sure they will get you back and running.

 

is it loading new rounds with each stroke?

 

with the lower separated, do the bolt and charging handle go back and forth with no issues?  is the buffer tube all gunked up?

[DesertTortoise]

Does it lock back on an empty mag when you cycle by hand ?

 

 

[Mban2]

1 hour ago, DesertTortoise said:

Does it lock back on an empty mag when you cycle by hand ?

 

 

Yes it locks back by hand, and there seems to be no issue with the feeding on the next round, or extraction and ejection of the spent casing.   I filmed it on slow motion on my phone and it appears that it the bolt is going all the way to the rear when it cycles

[inertia]

Possible but rare to outrun the cycle, try adjusting gas by starting low enough that it wont cycle and work you way up slowly with only 1 round in the mag.  Other possibility is if the gas block was ever removed it could be misaligned, certainly it wouldn't leave JP that way but if someone monkeyed with the gun later you could get just enough off of the correct location that gun runs but wont generate enough gas even wide open. If it has a SCS do you know if the springs or weights have been altered?  Last option is your ammo is just very under loaded so your under gassed but with a aluminum carrier it doesn't take much... try a few different loads?