GBBR rate of fire decrease

[Sacre]

So I understand so far that when you go full auto with a GBBR, it seems to slow down drastically by the time the mag is empty. So basically 13-15RPS, to 5rps,

Is this worse in some guns than others? or pretty much the same for all?

Does this happen on the first fill of a magazine, first time firing? or does it take a few mags before this starts to happen?

I've noticed on a lot of youtube videos their GBBR's slow down pretty quickly by the time the mags empty. Whereas you get the rare one where the gun can fire all 30 rounds without slowing down

Confusing a bit, would an experienced GBBR user please fill me in?

I have here a KWA LM4 Magpul Edition GBBR

Cheers

[pancakedestroyer]

Its cause the magazine is usually low on or out out gas.

[kullwarrior]

Originally Posted by Sacre

So I understand so far that when you go full auto with a GBBR, it seems to slow down drastically by the time the mag is empty. So basically 13-15RPS, to 5rps,

Is this worse in some guns than others? or pretty much the same for all?

Does this happen on the first fill of a magazine, first time firing? or does it take a few mags before this starts to happen?

I've noticed on a lot of youtube videos their GBBR's slow down pretty quickly by the time the mags empty. Whereas you get the rare one where the gun can fire all 30 rounds without slowing down

Confusing a bit, would an experienced GBBR user please fill me in?

I have here a KWA LM4 Magpul Edition GBBR

Cheers

Endothermic effect
Typically due to overfilling result in liquid spewing out.
Mag dump for gbbr are typically bad.

You can reduce it via avoid dumping mag, use lighter boltcarrier, and avoid overfilling

Sent from my HTC-Z710a using Tapatalk

[Sacre]

How do you avoid overfilling? Do you just count to 8 while filling or something of the sort?

And wouldn't this number increase as your giller tank starts to lose gas/pressure?

[Brian McIlmoyle]

As the liquid expands to gas in the magazine it results in cooling.. the cooler the magazine the less the gas expands.. resulting in a pressure drop inside the magazine.

the faster you shoot the greater the cool-down effect.

all guns that fire from gas in the mag suffer from this.

The specific properties of the magazine and the demands for gas of the gun can have a effect on this. Smaller magazines will suffer more than larger ones.

Ambient temperature also has an effect .. when it is 30c out you don't have many issues with this.. if you are trying to shoot below 10c .. you will have huge issues.

turn back to you highschool Chemistry.. properties of gas expansion are dependent on the temperature and the surface of expansion.

shoot semi.. or short 3-4 round bursts .. and you should be ok.

[Brian McIlmoyle]

Originally Posted by Sacre

How do you avoid overfilling? Do you just count to 8 while filling or something of the sort?

And wouldn't this number increase as your giller tank starts to lose gas/pressure?

Overfilling is not really possible.. the mag will only hold so much gas in a liquid and gaseous state.. if it is really cold out you may be able to get more liquid in.. but for that to happen it would probably be too cold to shoot anyway.

as long as you are making sure your source tank is upside down when filling and you are transferring liquid to your mag the pressure in the source tank is constant at a given temperature as long as liquid is present.