Knex Machine Gun

Finally I have finished my newest gun. Because it doesn't work very well though I am not going to make an instruction for it. I just thought that I would show it off and perhaps have somebody make it better.
After having spent probably 2 months on it and still not working I have decided to post what I have.
Pros- Can be tilted up
actually looks like a machine gun/gatling gun
it fires from a mag.
most of it is pretty strong
when it did shoot it shot 20 feet
Cons. The crank part of the gun is very bendy
the mag jams all the time.
the barrel doesn't spin very fast
trying to pick it up sometimes it breaks and falls
not really inventive