G&G midcap feeding issue

[Cocha]

Hello everyone,

I recently bought (used) 6x G&G midcaps. I tried them on a PTS Masada with around 20 bb's each just for a check and all seemed to work properly.

During my first game with these magazines, one of them (fully loaded) didn't want to shoot except for a random bb being shot as expected, pushing it towards the receiver didn't seem to change the result.

 

Back at home I took apart and tried various solutions found on the internet:

- remove this piece ;

- clean and lube with silicon;

- stretch the spring.

 

Nothing seem to work. What bugs me is that I can easily load it and then unload it by pulling the latch near the lip of the magazine.

 

Do you have any more tips I can try?

 

 

Thank you all in advance

[Asomodai]

Mid cap syndrome. The fully loaded mag is pushing the bb's with too much force into the hop chamber and air nozzle mechanism. You need to break in the mag spring. 

[Adolf Hamster]

As above

 

A short term fix is to intentionally load 10-20 rounds short of capacity and just run them that way.

 

A stub of inner barrel is a handy tool to extract a set number of rounds from a mag.

[Rogerborg]

Yup, midcap syndrome.

 

If you have a mag that works, you could measure it up against the G&Gs to compare the exact dimensions, particularly where the feeds are. There can be a surprisingly big difference, and even half a mm can cause problems - you might need to shim or remove material from either the front or the back of the mag to get it perfectly aligned with the hop unit feed tube.

 

The other thing you could consider is flaring the cylinder head tube to give a snugger fit with the air nozzle and stop it going owt skew on't treadle when BBs are pressing up against it.  Negative did a video on it a while back, but it's just a case of very gently tapping a tapered punch into the tube to spread it out slightly until the nozzle stops weeble-wobbling around on it. Again, tiny fractions of a mm can alter the behaviour.

[Cocha]

Thank you all, I'll double-check the differencies with the other magazines.

 

@Adolf Hamster, I've never heard of that, you'd use that in conjunction with the small latch of the magazine?

[Adolf Hamster]

28 minutes ago, Cocha said:

 

@Adolf Hamster, I've never heard of that, you'd use that in conjunction with the small latch of the magazine?

 

You drill a hole and pin one end, then push the other into the mag like it's the feed tube of the hop unit.

 

It might take a bit of wiggling but it'll pop the bb's right out.

[Lozart]

You could also try swapping out the tappet plate spring for an upgraded one. Then you can use your midcaps fully loaded.

[Rogerborg]

2 hours ago, Cocha said:

@Adolf Hamster, I've never heard of that, you'd use that in conjunction with the small latch of the magazine?

 

You just need a tube that's approximate the same inner and outer diameter as a hop unit feed tube, i.e. when you push it into the top of the mag, it moves the latch and BBs can feed up it.  A piece of inner barrel works, or any 6mm ID tube with about a 7mm OD.  As a random discovery, I noticed that the purple inner plunger from a small Calpol syringe is hollow inside and has the right dimensions. So I cut the front off one of those and use that now - you can hold your thumb over the end and press it in to release a few BBs at a time, or direct it into a bag or bottle if you're emptying the magazine.