Originally Posted by cruzito187
So what I ment by slow is velocity.
It's a rdw bravo. Same body and great box ad m4.
So yesterday I notice that the nozzle wouldn't go back.
It was jamed. So I opened the gearbox again and when I put it back together I pushed the nozzle and it was ok. I shot a couple of times and it got stuck again. Maybe Im not puting the sector gear in the good position. When I opened the gear box again I notice that the sector gear turned but only half way. I bought this gun used and there is shims and a plastic thing on sector gear. Does it mean that it was modified? I really whant to do this my self. Don't whant to give up.
Don't sweat where the nozzle is or if you can push it or not. After every reassembly you should be able to push the nozzle in and have it spring back...but after the first shot it'll be held back some ammount by the post on the sector gear.
If it shoots a BB every time...you've got things mechanically assembled correctly.
If you're getting inconsistent velocities, you've got either an air leak somewhere or an inconsistent air seal somewhere. Usually it's between the tip of the nozzle and hopup rubber, but it can be from o-ring around the piston head too, or from a poor fit between the nozzle and the cylinder head nozzle. If you took the cylinder head off and nicked the oring around it when you put it back into the cylinder...then that could be a problem too. Many hopup units have a spring that pushes the hopup unit back against the mechbox to keep a good seal. If the hopup unit is not seating right up against the mechbox shell or if it's bouncing around randomly you'll get odd velocities. Etc...
Anyways...search for "compression test" and "air leak"...there's lots of threads about it.
Also...tightening things down too much can cause the parts to be pulled out of alignment. These things are all that stiff/robust. Sometimes cranking the screws of the grip on too much will skew things...same with the rear stock screw (on M4's). Try assembling things snug but not tight and retest.