google:
" how does an aeg cut off lever work "
in semi the selector plate is allowing the cut off lever to rise up (cam on sector gear)
and as it rises with switch engaged/trigger pulled it lifts the switch trolley up/away from trigger
which flies backwards cutting off switch circuit stopping the gun cycling
the little spring returns the cut off lever to rest allowing the switch to drop so trigger can relatch onto it
in auto the cut off lever is disengaged as it is pulled up out of the way
(said google it coz it probably will get a bit confusing as I try to explain it)
However......
on most old skool mechanical switch aeg's there is a "dead zone"
this is where when firing on semi the trigger is released too early and the cut off lever has not fully returned
Trying to fire gun is this state will have the trigger & switch trolley not latching correctly - often slipping off each other
or feeling a bit stiff....
DO NOT FORCE IT you can damage it which sounds like it may have happened perhaps to give odd symptoms
what you are supposed to do in this instance is switch to auto - fire once or nudge gun's cycle past this dead zone
(it is where cam is still lifting the cut off lever a smidge)
The operation of semi/auto is basically where the cut off lever is slipping under the switch to lift/disengage it on semi
or
slipping over the switch on auto so the cut off lever has no effect on the trigger/switch mechanism
spring itself - not normally sold on its own, normally in a v2 spring set for about fiver
http://www.ak2m4.co.uk/zci-gearbox-spring-set-v2
you could chop up say a clicky biro pen or something like that to find a similar spring
(yeah that bastid spring is tiny and boy does she fly well - lost a couple of those mofo's)
The only concern is that if the trigger/switch has been forced a number of times in the " dead zone "
it may have caused a little wear on the switch trolley or other parts involved
was gun new or s/hand - most parts will fit in a G&G ok but some parts are more compatible than others
and may need a tiny modification to get them working perfectly....
either new and been forced in dead zone
or s/hand and not serviced/repaired 101% correctly on mechanical side of switch
some M4 selector plates are slightly slightly different to others I have noticed
not just some are thicker/thinner but the selector cut out or semi point can be different
(an area that is modded/removed to disable auto firing on dmr's)
so the selector plate might have worn or failed to lift the cut off lever 101% correctly
impossible to say the exact single cause - take a few pics maybe so we can see & maybe rule out stuff
c'mon Santa - where's my f*ckin' bike !!!!!!
(04:30am xmas morning and no pressies yet - geriatric old fart)
Merry Christmas