M4/M16 hop up assembly
 

I need some instructions on how to put an m4/m16 hop up unit together. I accidently took mine apart

It's really basic, if you look at the way you can fit the parts together, am sure you can figure it out. The parts only fit in place one way, the only real way to do it wrong is to put a gear or two on upside down.

what about the rubber and the brass ring? i can't get the barrel and them to fit in proper

Fit the rubber on the end of the barrel, make sure it's on correctly. Then put the barrel into the hopup unit and finally push the brass ring into the hop up. It should fill the gap between the barrel and the hopup.

ok thanks a lot, i got it know