G&P M4 Over-hop problem.

[Amos]

So I've got a G&P (Re-built by WGC shop) M4... No matter what I set the Hop to the BB flies out about 20 yards then makes a very sharp curve upwards. (Tried it on .20's, .25's, and .30's.)

The gun fires 335 on .20's

I took everything apart and noticed that the hopup chamber didn't have a spring on it... But apparently some G&P guns don't come with that spring...

My thoughts are that it's due to the missing spring... but that should provide LESS hop... and my problem seems to be TOO much hop.

Any words of wisdom?

[Styrak]

Problem most likely solved by moi.

[Skladfin]

improper assembly of hop up rubber is the first and foremost reason for this. The hop up rubber and bucking is probably misaligned and the arm that pushes down on the bucking is not touching the bucking.

and the spring on the hop up unit probably have nothing to do with it. But its VERY reccomended that you have a that spring.

you can crack open any click pen, and take the spring inside, cut it to the proper size and put it on.

[Amos]

Awesome will do...

Now I just gotta wait for it to stop raining so I can go test this

[SDS_ShooterMcGavin]

Originally Posted by Amos

Awesome will do...

Now I just gotta wait for it to stop raining so I can go test this

Were getting hit with it right now... JUST after I washed my car..

[Amos]

Okay... so I threw in a guarder clear rubber and bucking...

And even with the hop up all the way off... I'm still having the same over-hop problem.

Any more suggestions?

[Fly 9]

Could be a dirt thing
The barrel's clean? BB hitting anything on its way out? BB's clean? Mag clean?
Did you just oil anything? You could have gotten oil into something that comes into contact with the bb's.

Just a thought

[Amos]

Originally Posted by Fly 9

Could be a dirt thing
The barrel's clean? BB hitting anything on its way out? BB's clean? Mag clean?
Did you just oil anything? You could have gotten oil into something that comes into contact with the bb's.

Just a thought

Swabbed the barrel until it came out clean, looked down it, doesn't appear to be any scratches or abrasions. BB's are brand new KSC perfect .25's, the mag's a high cap, and it doesn't have any foreign things inside of it.

And nothing's been oiled :/

This one's starting to puzzle me.

[digital_blue]

Are you sure that the barrel is straight(both inner and outer)?

[The Saint]

Try H-nubs?

[Skladfin]

its obviously not assembled right, how did you go by putting in your hop up rubber?

[militia]

i had a problem like this before, it was my gas tube, it got caught ontop of the hop up rubber.

[ownzyouall]

I've had the same problem before as well. Except my bb's shot downwards instead. I replaced both my hop-up rubber and bucking. Gun worked great ever since. Careful when aligning the bucking, its a real pain to get it in the right place.

Cheers.

[Amos]

My bucking is placed correctly, same with the rubber... I've worked on plenty of guns and I know how to install a new rubber... That's why this is puzzling me so much.

I'm going to try to drop some one else's barrel and hopup into the gun to see if it works (Which in theory it should work perfectly.)

I should dis-assemble the hopup and re-assemble it.. The "Professional Guntechs" at WGC shop may have screwed up on something there.

[Jaaks]

Are u using a soft or hard hop up rubber? because I'm having the same issue and I"m gonna switch to a hard hopup rubber which should not affect the bb's as much as they leave the barrel. I was told the reason behind it but I cant remember how to explain it well but give that a try.

The spring is useful as well to make sure the hop up unit is sitting flush against the mechbox so that there is no air loss.