Hop Up design modification to fix design flaw for airtight seal HELP

[Whambham]

HI Guys simple question on Hop ups i have a G&G Top Tech gr16 commando and while installing some bucking i notices a hole in the hop up chamber right on below the NUb holding arm directly above the magazine feeding barrell.

i was under the assumption you need to have an airtight seal in your hopup but on testing the barrell and hop up i found a considerable amount of air was lost through this hole.

i have included a pic of the hop up and were the hole is.

my questions

is this normal for all hop up chambers or just mine.
can i block the hole to create an airtight seal.
is their a specific function of this hole.

G&G hopup design.jpg

[Genista]

Re: Hop Up design modification to fix design flaw for airtight seal HELP

Can you take a picture of the hole itself?

As far as I know, the only hole in the top of the hop unit should be where the arm pushes the nub through to the hop rubber. This is sealed by the hop rubber itself.

If you have hole directly above where the bb's feed vertically in to the hop unit then that sounds odd (though it would be behind the end of the nozzle when the piston was released.)

A picture paints a thousand words.

[Whambham]

Re: Hop Up design modification to fix design flaw for airtight seal HELP

hole on top of hopup.jpghere is a pic of the hole if you look from below the hop up chamber i think a bb is suposed to stay in their

[madwelshman]

Re: Hop Up design modification to fix design flaw for airtight seal HELP

You either have a torn hop rubber or it's loose as a hookers vag... Other than that, the only leak can occur at the neck of the hop rubber when it marrys up with the air nozzle.

[Whambham]

Re: Hop Up design modification to fix design flaw for airtight seal HELP

Nope nothings torn everything is snugley fit here is what i think happens in the diagram but the flaw is air leaks out the hole is their to prevent double feeding i think

Diagram blueprint.jpg

[desolation91]

Hold on lad.. Doesnt the nozzle create the seal once it pushed the bb forward into the hop bucking?



Sent from Samsung Galaxy S2

[SAS Scott]

Re: Hop Up design modification to fix design flaw for airtight seal HELP

Hold on lad.. Doesnt the nozzle create the seal once it pushed the bb forward into the hop bucking?



Sent from Samsung Galaxy S2

Yep.. That hole shouldn't cause an air leak.

[Whambham]

Re: Hop Up design modification to fix design flaw for airtight seal HELP

the nozzel is directly behind the hole so no some of the air will escape if the nozzel was under the hole then the bbs will not feed through the mag as the hole goes directly above the mag feed hole think of it as a cross and a hole in each end nozzel stops before the lines cross the fact that i tested with a few bbs in the chamber and felt air leaking out of the top Major design flaw

[SAS Scott]

Re: Hop Up design modification to fix design flaw for airtight seal HELP

The hole shouldn't effect anything IF you have made sure your hop rubber has a perfect seal with your barrel and nozzle.

If there is air leaking out of that hole it is most probably that there is an air leak between the nozzle and hop rubber.

[Whambham]

Re: Hop Up design modification to fix design flaw for airtight seal HELP

il just buy a new hop up unit that doesnt have any design flaws thanks anyways

[desolation91]

Yeah can you take a good infocus picture from behind so we can see the hop rubber. You should be able to see around the end of the barrel. Or if you can see it and you haven't changed it in a while i suggest you change it and try again

Sent from Samsung Galaxy S2

[Whambham]

Re: Hop Up design modification to fix design flaw for airtight seal HELP

its ok i found what i was looking for

That hole is hypothetically supposed to prevent double feeding by making sure the bb does not roll forward in the hop-up chamber until the air nozzle pushes it.

its in all Plastic G&G hopups you can mark this as resloved

[Gavin]

Re: Hop Up design modification to fix design flaw for airtight seal HELP

Maybe being / having a blond moment but
The nozzles contact / penetration with the
Rubber and the fitting tightness with the
Barrel are the only leak places ???
PLUMBERS TAPE around the end of the rubber
And c clip = 100% seal

[Genista]

Re: Hop Up design modification to fix design flaw for airtight seal HELP

No Gavin, the hole in question is separate to that.

Interesting discovery but it sounds less than helpful.

That said it should only be back pressure you're feeling, not a main leak. Does it chrono ok?

It'd be interesting to hear back from you about what difference a new hop makes.