G&G M4 Pneumatic Blowback

[IceTray]

Well, there are some goods and bads to it, I like it as a primary, its pretty reliable.
If he plans on upgrading it or taking out the bloody pin in the front, there's a chance he'll never get it back in, I've had the gun cleaned and reassembled for about 6 hours, except that one damn pin won't go back in all the way. (Might just replace the lower receiver)
It boils down to preference and budget; I wanted an armalite, and I had the money to afford it, so I picked up this one from Jeff. I'd suggest it (or the non blowback from G&G) to any one of my buddies looking for one.

Hoping to have a video up on the weekend.

[ujiro]

Originally Posted by IceTray

If he plans on upgrading it or taking out the bloody pin in the front, there's a chance he'll never get it back in, I've had the gun cleaned and reassembled for about 6 hours, except that one damn pin won't go back in all the way. (Might just replace the lower receiver)

Wow, impossible. As I said previously, it ended up taking a piece off of my metal receiver from G&G. From hammering it open. Pain in the ass. What you can do is disassemble the whole pin assembly. There is a little hole on the front of the lower receiver, in line with the front pin and that little pin that sticks into it to keep it on the lower. You can push that little pin in, then slide the whole front pin out. Then, there is a spring behind that tiny pin when you take it out. Clip the spring just a tiny bit (read: a few mm max) to stop it from pushing too hard on the front pin. That is what I am planning on doing.

[IceTray]

To be honest, I planned on removing the pin like you, but I was going to replace the pin with a different one, that has a smaller diameter, hoping it doesn't turn into the madness this is being, the pin is still sitting 3/4th into my receiver, haha.
If your plan works, let me know though

[ujiro]

Well it would, except after I epoxied the receiver, a little got in the way of the hole, so it was a little tight and now the pin wont come out of its slot.... The little pin that is.. I will keep you posted though.

[m102404]

After messing around with a couple of the G&G M4 blowbacks, I've figured out a way to reassemble without stressing the front pin (or at least it worked on the ones I had on the bench...not sure how many variants there are of these things out there).

With the lower receiver completely empty (except for the selector switch and fake bolt release) try the following in this order:
1. Insert mechbox into lower receiver
2. Insert flora pin (the cross pin that is just above the trigger)
3. Install the mag catch
4. Slide the upper onto the lower (balancing the charging handle and little spring as you slide it on)...route wires as necessary (the ones I had were front wired).
5. Once the upper is on the lower, slide the front pin in...it should go through with little to no resistance.
6. Push through the rear pin...it might be tight-ish, careful
7. Install the stock spacer and stock (stock pipe in my cases)...don't over tighten
8. Install the grip/motor/grip plate

The plastic G&G is using is brittle...I don't think that it can take much stress/strain.

As an aside, the hazy-clear plastic that ICS is using is quite thick and has some give/flex to it (i.e. if you squeeze it hard it'll flex, not seem to crack like the G&G). All the guys that I've passed it around to (with the busted G&G receiver to compare) have all commented how much better the ICS receiver plastic seems to be.

Best of luck,

Tys

[IceTray]

Originally Posted by m102404

After messing around with a couple of the G&G M4 blowbacks, I've figured out a way to reassemble without stressing the front pin (or at least it worked on the ones I had on the bench...not sure how many variants there are of these things out there).

With the lower receiver completely empty (except for the selector switch and fake bolt release) try the following in this order:
1. Insert mechbox into lower receiver
2. Insert flora pin (the cross pin that is just above the trigger)
3. Install the mag catch
4. Slide the upper onto the lower (balancing the charging handle and little spring as you slide it on)...route wires as necessary (the ones I had were front wired).
5. Once the upper is on the lower, slide the front pin in...it should go through with little to no resistance.
6. Push through the rear pin...it might be tight-ish, careful
7. Install the stock spacer and stock (stock pipe in my cases)...don't over tighten
8. Install the grip/motor/grip plate

The plastic G&G is using is brittle...I don't think that it can take much stress/strain.

As an aside, the hazy-clear plastic that ICS is using is quite thick and has some give/flex to it (i.e. if you squeeze it hard it'll flex, not seem to crack like the G&G). All the guys that I've passed it around to (with the busted G&G receiver to compare) have all commented how much better the ICS receiver plastic seems to be.

Best of luck,

Tys

I'll actually give this a go this evening sometime, and if it works, I'll let you know. Preferably, hope it does though, haha

Edit:
Well, I did some shot tests using pmags today, they were 50 round vn style pmags, I didn't notice any feeding problems, the mags don't whole heartily accept bb's from a speed loader, but the gun itself feeds fine from these types of pmags.
After following your guide I actually had no difference in results of getting the pin back in, unfortunately. The farthest I can get the pin in, is about 3/4's, the last loop from the lower receiver sits down from the hole, so the pin won't go through, even regardless of how many ways I try from reassembling, lol.

[IceTray]

Just a small video done to show the blowback, and an small accuracy test on semi and full auto. Provided it doesn't rain tomorrow, I'll do a larger distance accuracy test.
YouTube - G&GM4Pneumatic

The blowback actually goes as far back as the mechanism allows. So basically, it goes as far back as you can pull.

This is a screencap from the video above, the angle is unfortunate, but its actually open as far as it can go.

[KenC]

G&G never made any NiCd 8.4V 600mA mini batteries. And the label on your battery surely is not from G&G. See for yourself: http://b2b.guay2.com/eng_part/eng_ba..._battery_1.htm

All Blow Back series GR16 and MP5 should have come with this:


Also, even with a normal brand new 8.4V 600mA NiCd mini battery, the performance would not be that bad, I suspected your battery might be a used one.
Your 9.6V 1400mA NiMH that should have come with this gun might have been SWITCHED OUT before the package was shipped to you.

I would check with your supplier immediately.

The Blow back is there to look cool, there is no performance related features associated with it

Ken
007Airsoft

[KenC]

EDIT:

Mine GR16 Blow back's actually have the same internals as Mach 1's. They all have the Plastica series internals.
So the only difference is that mine have C8 Maple leaf receivers, while Mach 1's have combat machine receivers.

Luckily I was able to edit this post within 10 mins of posting the wrong info.

Ken
007Airsoft

[panzergrenadier]

Yeah I got mine from Mach1 and it's one of the Combat Machine ones...

[panzergrenadier]

Also I have a feeling that some of the Externals on the REAL G&G rifles differ from the Combat Machine ones...
Ken, Do you have any Detailed pictures of the ones you have?

*EDIT* I might be wrong about the externals... the Schematic Drawing from the G&G website shows the same thing as the Combat Machine one.

[peacekeeper]

From what i understand the combat machine g&g line is there basic or entry lvl aeg and then the standard G&G is there better line and toptech is there high end guns

[KenC]

But the mid line (G&G) has a regular branch (all metal) and the plastica line......

[panzergrenadier]

Originally Posted by KenC

But the mid line (G&G) has a regular branch (all metal) and the plastica line......

Do they make the All metal Blowbacks with a clear lower?

[KenC]

No, the only ones so far is the GR16 Carbine (M4A1) and MP5 A4. Only two models.

You can easily build your own vairants though, if you have the right parts.