GR16 misbehaving

[ronin677]

So my GR16 was firing ok but started to fire bb's all over the shop at the end of my last game. I have now taken apart the hop up unit and made sure it is all ok (it all seems to work as it should manually turning the gears). I have cleaned the nub and the bucking (all looks fine). The hop up looks centrally placed once the weapon is back together.

 

But when I fire it it seems as though bb's are going in all directions and I really mean all directions (almost as though they are sometimes leaving the barrel at 90 degrees), it also seems as though it is misfiring as well, ie bb's are not always coming out i think)

 

I am at a loss what to do

 

any advice?

[Lozart]

Have you checked there's nothing obscuring the barrel exit? Nothing stuck in your flash hider that might be skewing the rounds as they leave the barrel?

[Adam3088]

Checked inside the barrel to make sure there's no crap in there? Might be worth giving it a clean just incase.

 

If you turn the hop up fully off is it any different?

 

Edit: bah, ninja'd

[ronin677]

The barrel is clean and dry, absolutely no obstructions at all. The rifle behaves the same whether the hop up is turned up or down. I have double checked the hop up is working and centralised again but still no difference to performance

 

[Adam3088]

If the barrel is fine and the nub is working properly, only thing it could be is the bucking I guess? Might be worth double checking it's on properly.

[ronin677]

Double checked the barrel and flash hider and everything is in mint condition. It might be me but it seems as though bb's might even be coming out broken (I might just be being paranoid now though)

[ronin677]

If the barrel is fine and the nub is working properly, only thing it could be is the bucking I guess? Might be worth double checking it's on properly.

checked and doubled checked. even cleaned it with soapy water and dried the bucking before putting it back

 

I am at a complete loss. I am not getting a single bb to fire straight or even close to straight

[Adam3088]

Hmm, what about the air nozzle? If you fire into something soft do they really come out of the barrel shattered?

[ronin677]

What is the air nozzle? Is this the tube that sticks out of the gearbox? I will try to fire into something where I can collect the bb's and see what condition they are in

[Adam3088]

Yup, that's the one, black plastic tube coming out of the gearbox.

[ronin677]

Well i just fired a few rounds into a catchment box and they are not coming out as shattered, so I guess thats something to be thankful for.

 

I've checked the air nozzle also for any obvious damage or obstruction and it looks clear and ok

[Lozart]

Have you got a batch of cheap and nasty BBs?

[ronin677]

Have you got a batch of cheap and nasty BBs?

I don't think so. These are the same ones that I have been using at my site and they were fine all day until the end of the day when my gun started playing up. they are 0.25g

[Lozart]

Hmmm. Well, I'm stumped.

[Adam3088]

Likewise, cant see how anything on the gearbox end could have any effect on this.

Does it sound any different to normal when firing?

 

Other then that all I can recommend is recording it firing and upload it somewhere for people to have a look.

Also when you say firing out at angles, do you mean left + right as well as up + down?

[ronin677]

Likewise, cant see how anything on the gearbox end could have any effect on this.

Does it sound any different to normal when firing?

 

Other then that all I can recommend is recording it firing and upload it somewhere for people to have a look.

Also when you say firing out at angles, do you mean left + right as well as up + down?

I'll try to capture it firing for you all to see. It fires all over the place, no set pattern, left, right up and down. Sometimes so skewed i don't even see where its gone

 

I am completely baffled because an an engineer I can't see why it isn't working

[ronin677]

The only thing I can think of is that my hop up unit is misaligned or something. I've also had problems fitting the wires from the gear box, past the magazine housing and hop up, and then through into the hand grip.

 

Does anyone have a photo looking up into the magazine housing of their M4. I would just like to see how other peoples wires are routed.

 

cheers

[Samurai]

Just guessing: maybe the nozzle or the tappet plate broke and somehow multiple BBs are fed for each shot so they hit each other in the barrel. Does it fire that badly on single shot too and is there only one BB per shot?

[ronin677]

Just guessing: maybe the nozzle or the tappet plate broke and somehow multiple BBs are fed for each shot so they hit each other in the barrel. Does it fire that badly on single shot too and is there only one BB per shot?

Single shot and full auto and yes I believe that multiple bb's are being fed at the same time. What is the tappet plate?

[ronin677]

All sorted

 

Its not as bad I had thought. The problem it turns out (he says rather sheepishly) was the outer end barrel assembly. It had obviously got knocked at the last game and moved slightly (but not noticeable to the naked eye). The bb's were then hitting this as they existed the inner barrel.

 

So I reattached it and the rifle now shoots perfectly, even better than before (not surprising considering the overhaul its just had lol)