My Semi shoots Auto
 

Hello everybody~
I am located in Hong Kong and just recently bought a full-auto Classic Army M15A4 airsoft gun which I played with yesterday.
Everything was fine until today I just tried some dry shooting (without bullets) and suddenly the gun would start shooting in 2-3 bursts in Semi-mode. Also, sometimes the gun would shot full-auto non-stop in Semi-mode. I'd say it only shoots semi in Semi-mode 50% of the time.
Since I just bought the gun a few days ago I still have a one year warranty on it. Just wondering what you guys think and if this is a common problem or not.
Thanks for any input. =)

Most airsoft guns default to full auto; they need an interrupter to stop them. Take it back or take it apart and repair or replace the semi interrupter.

Cheers! I will take it back and explain the problem to them. =)

The cutoff lever is probably worn.

Thanks for your response.
I was wondering, since I just bought the gun a few days ago, is it common for the cutoff lever to be worn out so quickly? Or did I just buy the wrong gun at the wrong time?
Another thing, would you say it's easy and quick to replace the cutoff lever? I am asking because I don't want the shop to tell me it's going to take a week when it can actually be done within a few minutes/hours.

EDIT

Would this be an explanation for the problem I described earlier in this topic?
http://www.airsoftcanada.com/showthread.php?t=25310
I can remember this has happened around 2 times during the 6 hours I played.

The time it takes just depends how good the person fixing it is or how much attention they put into it or how much free time they have or how much you pay them. It's the same as every other job of taking the gun apart and disassembling and closing the mechbox. You can do it in 30 minutes or it can take you 3 hours. If the shop is busy, he might not get to your gun for a week unless you pay him more. Who knows.

The link you included is completely different, that is just poor trigger pulling and weak batteries leading to the motor not turning over completely on every cycle because not enough current goes through since the trigger is only making partial contact or even shorting out or the battery is simply not providing enough juice per cycle. If you think that is the issue, just buy a 7.4v or 11.1v lipo battery which are plentiful in HK. It will also reduce trigger lag.

i have sort of the same problem...sometimes my m4 shoots bursts when on semi mode...any ideas?

3 things to check
1) cut-off lever spring - put a beefy spring in it to solve the problem. The Cut-off lever needs a certain "push" to get the cut-off lever to cut-off the contact block

2) Worn cut-off lever

3) Worn moving contact block