Hope placement issue

[Boo-Sabum Ben]

Having a problem with my M4s hop unit. It's a normal 1 piece, and put it all back together to find it's not feeding right. Problem is that the bbs aren't reaching the top of the hops feed tube as the air nozzle is a tiny bit over the top. I can push the hop unit forwards slightly and feed a single bb in at a time and it works fine.

What can I do to make sure they reach the top of the tube everytime?

Also, the gearbox has dropped down to semi only, very randomly. The gearbox before was working on auto only, was rebuilt completely. Worked flawlessly, now only seems to be working on semi after I put the rear stock pin in

[Montesa77]

Re: Hope placement issue

For the hop problem; can't you shave a tiny bit off the air nozzle? And for the semi problem; is the body touching the plate?

[jagillham]

Re: Hope placement issue

The air nozzle will move backwards as part of the cycle to let a BB in. So should overlap

Have a look in the hop unit down the barrel, with the hop off. Should be a perfect circle, if not the rubber has got scrunched up.

Edit: As such....

[Boo-Sabum Ben]

Hop seems fine, it's letting bbs pass through. At the moment this is how it works.

Pop bb in the feedtube, stops at the air nozzle. Push the hop unit forwards against the spring on it, and it pops down towards the hop. Release it so it pushes back against the gearbox, fire, and hey presto. It's as if I'm missing some sort of buffer part between the gearbox and hop unit!

[Boo-Sabum Ben]

Air nozzle is about 1 3rd of the way over the top, and rather than moving back, seems to just jiggle on the spot. Could be the problem?

[jagillham]

Re: Hope placement issue

Sounds like it is not connected to the tappet plate correctly then.

Either not put on correctly or broken!

[Boo-Sabum Ben]

God damn it. My tech only just put this thing back together. Guess he did it wrong!

[Montesa77]

Re: Hope placement issue

What jagillham said. If its not moving the tappet plates broken or the nozzle is broken/disconnected. Mabye he forgot to put the spring on.

[jagillham]

Re: Hope placement issue

With the gearbox out, it should have very little sideways movement. If you can push it back and forth more than a few mm's without any resistance then it's definitely that.

[Boo-Sabum Ben]

Pushing it back and forth doesn't move it at all, remembered that when I put it in! My skorpion gearbox did move, but thought it was just differences between gearboxes!

[Montesa77]

Re: Hope placement issue

Jam donuted?

[jagillham]

Re: Hope placement issue

Fire off a few shots on semi, then see if it's the same! Should be able to see if it moves too at that point.

[Boo-Sabum Ben]

...?

[Boo-Sabum Ben]

Don't have the Skorpion anymore lol. Will go get the AK!

[Boo-Sabum Ben]

The workhorse rifle works as expected, so yeah mines knackered. Got a new gearbox coming off here in the next few days hopefully so will just drop it in and should be good to go! Thanks for the help guys :D