firing problems KA M4 AEG

[icdbko32]

not sure if this is proper forum but I don't know where else to put this, if i'm wrong please just let me know.

so I just recieved a new King arms M4 aeg and it's having firing problems already.

the problem is when I go to fire either semi or full auto it only fires sometimes and when it doesn't fire it sounds like it doesn't do a full cycle and doesn't fire the bb. every once and a while though it does fire a bb. I turned the gun over and watched what happens when it fires and it seems that the bb travels forward and bounces back like it doesn't have enough air to push it or its being obstructed. if you muzzle load a bb, the bb travels just fine down the barrel.

things i'v tryed so far:
- charged the battery with a smart charger multiple times
- used different bb's to no avail
- made absolutely sure there is no barrel obstructions

from my limited knowledge of aeg's im wondering if it's just the upgraded spring in it not allowing it to cycle properly seeing how fps currently is at the 430-450 mark.

if anyone knows how to remedy this please let me know, help is greatly appreciated

[89db]

Maybe motor sits too high.
Watch this and near 2:00 he is putting the motor too low and too high. see if the problem match the symptoms

Airsoft Tech Tips: Motor Engagement & Adjustment for Airsoft Electric Guns AEG - YouTube

[icdbko32]

tryed that but still can't get it to work

[Rooster]

Check your motor connections. I test fired mine last night (brand new also) and it fired a few shots then nothing then a few more. Turned out that the connector was loose on the motor tab and wasn't making a solid contact.

[SMIC4]

What type of battery are you using? Maybe the battery isn't strong enough to pull the spring, or maybe the battery isnt able to hold enough charge. Try a different battery.

[icdbko32]

only battery I have right now but ill see if i can get one, the battery is new as well and its a 9.6 1600Mah NiMH

[SMIC4]

if you have a multimeter you can check the voltage to see if the battery is holding a charge!

You can also try removing the upper receiver before firing the gun to see if the gun is cycling. Make sure the piston and nozzle is moving correctly. If it's cycling, then the battery isn't the problem.

If the battery isn't the problem, I suspect it's the piston head. KA piston heads seem pretty crappy!

[icdbko32]

battery is good

I may have found the problem, not sure of the proper name of it but I beleive it's the BB retaining o-ring that is housed before the hop up unit which prevents the BBs from rolling out of the barrel. I tested the piston for compression and compression seems fine.

[icdbko32]

does anybody else have any possible causes?