Power Issues

[Callum46]

Ive just bought a second hand G&P M4, I can fire a few shots on single and full auto and then there is no response from the trigger. For example, I can get at least 6 shots from single fire and there is no response from the trigger but if move it to full auto, the gun backs to life and starts to work. 

 

Im using a  7.4 LiPo battery at full charge.

 

Any ideas to what's going on?

[Misery]

imo i am probs wong but sounds more like its jamming up

[Callum46]

1 minute ago, miserydrift said:

imo i am probs wong but sounds more like its jamming up

 

How do you mean?

[Misery]

like somethings binding up then with the friction of the shots heat build up enough to jam it  then by time you change from semi to auto its cooled enough to fire again like i said im more than likely wrong bud just my 2 pence worth

[Adolf Hamster]

sounds like it's settling in a position where the cutoff lever is locking it up.

 

does it have a mosfet fitted? if so then possibly one of the first things to check is if it has active brake or not.

 

active brake on some guns (particularly ak's but can happen to m4's) can stop the system fast enough for it to be in a lockup position in semi.

 

switching to auto disengages the COL which is why you can use that to clear it.

[Iceni]

Check the fuse when it's running. I've had it where a new gun made the fuse glow but not blow. Once it started to glow the gun would slow down and appear to lockup, then once it cooled again the gun would work for a few more shots.

I suspect this happens because glass fuses are inaccurate with the blow current, And if you get one that's close to blowing but still holding on you find the resistance in the fuse can go really high and pull a lot of potential away from the motor.

If this is the case then buying a new fuse will solve it.

[johnnyj]

Sorry callum open up the gearbox good chance it's as the others say or your feathering the trigger and the switch hangs up on the block but 1 thing I have seen loads of times in older g&p guns is a snapped axle on the spur and it gives this exact symptom