Ghk Mag Dumping Gas

[Enid_Puceflange]

Hi folks

Looking for some guidance from the hive from members with experience of GHK issues. I recently bought this rif used , and upon first firing using one of the supplied Stanag mags , it dumped its guts (ignore polymer mag in video)

It HATES using the metal Stanag, it has settled and will work nicely with the polymer mags. 
I have checked the breech / battery and there is no shrapnel from smashed bb’s

it does look like the bolt holder didn’t go all the way forward in this attempt, but after checking, the metal mags are at best temperamental 

The polymer mags run as sweet as a nit

go figure 

 

[Enid_Puceflange]

Works a treat using the polymer mags

go figure 

 

[Chev Chelios]

I take it everything is new? What specific propellant are you using? Does it happen if dry firing? 

Somethings to check -

With the gun split when you cock the hammer does the valve knocker (the bit sticking in the magwell) retract all the way back? If not it could be resting on the valve impeding it closing.

Are the valves tight in the magazines? Again if the valves are sitting to fare out the valve knocker will not let them close properly. Should just be hand tight, torqueing will squash the brass.

Remove the buffer and spring, drop 5 10p coins into the buffer reassemble and try. You are short stroking the system to check to see if the bolt return is resetting the valve knocker quick enough. 

Split the gun, check to see if the G5 and STANAGS sit in the magwell at the same height. You are making sure the valves and knockers line up the same. 

Swap the valves over to one that works and give it a try.

Seals could be dry. Remove valves stick them in a plastic bag, soak in oil and work the valve making sure to get oil on the internal o-rings. Leave overnight. Doing this to make sure the o-rings have enough lube to function and are not impeding the return spring in the valve.

Let me know how you get on.

 

[Enid_Puceflange]

Thanks Chev

I will try your suggestions out

as I say, it’s fine on the polymers, the Stanag are the problem so somethings amiss with those mags ??‍
cheers

 

[EvilMonkee]

In addition to what Chev said, try purging ALL the air out then filling the mag.  It could also be an overfilled mag believe it or not

 

[Enid_Puceflange]

Thanks again folks , I will hopefully get to have a look at test firing this again on Sunday ?

 

[Enid_Puceflange]

In addition to what Chev said, try purging ALL the air out then filling the mag.  It could also be an overfilled mag believe it or not

Yup, seen a couple of videos & posts going on about a 4 second gas fill being best for its efficiency and consistency