Gun won't feed on full auto

[dgibbons]

I just replaced the gears in my m4 gearbox & upgraded some other parts.
Feeds ok on semi but not on full auto.  I put a G&P 120 motor & all worked fine
when I test fired it a couple days ago.  I went to chrono today & now the feeding
problem.

This is a different combat machine from my original post.

What did I do wrong?

It's a G&G combat machine.  I also swapped the air nozzle, piston head & spring.

Thanks for the help.

[wolfenblaze]

check ya air nozzle chances are it maybe not the right size. it has happen too my Custom built RPK. i switched the nozzel off it with a V3 Long instead of a V3 short nozzle. it could be ya have too short nozzle or too long

[kevindagee]

Do you think you can upload a pic?

[dgibbons]

Thanks for the replies.

It was the air nozzle.

Now I have a similar problem on a different combat machine.   

[dgibbons]

It was the tappet plate on the second gun.