Fused AEG Battery Query

[MrTea]

Hi everyone.

I've recently acquired an G&G MP5A4 which, from what I can find, is only supposed to run on 7.4v LiPos. When taking it apart to address a different issue I found that the gun is fused with a fuse like you'd find in a plug socket. I checked the fuse over but couldn't find a rating on it. After a bit of internet searching, 20Amp is supposed to be standard. Would it be possible to run this gun on 11.1v LiPo safely or does it absolutely require a MOSFET to avoid damaging the trigger contacts or will the fuse pop before that happens? I can pick up a super basic Gate X-ASR MOSFET for £20. I want to run on 11.1v as the 7.4v just feels sluggish.

Thanks for the input.

 

[Colin Allen]

The first thing to do might be to change the motor for something like an SHS or Rocket high torque one.  That will give you both better trigger response and a higher rate of fire.

If that fails to please you, you could run it on an 11.1v battery, although you would be inflicting more pain on the trigger contacts and moving parts.

if it is a rear wired solid stock version, a 9.9v LiFe battery, in conjunction with one of the aforementioned motors should bring a smile to your face while not overly stressing the gears etc.

if you are going to go for a simple mosfet, make sure that it is a hardwired one rather than one of the plug and play ones; the latter do nothing to increase the longevity of your trigger contacts.

Getting rid of the fuse and changing the connectors to Deans, if they are Tamiya, will also help.

 

[MrTea]

Thanks for the reply and the input.

So my current upgrade list i'm looking at is;

• High torque motor ~£35
  
• High speed gears - 16:1 or lower IIRC ~£20
  
• Hardwired MOSFET - A Perun or Gate Aster? A recommendation here would be helpful ~£70
  
• Changing battery connection to deans and fuse removal which should be simple enough ~£ however much some deans connectors and wires cost.
  

 

[Rogerborg]

Opinions vary (a lot) but a Big Dragon M140 motor, 11.1V battery, and a ~£45 Perun AB++ (already wired for Deans) does everything I need and more.  Pre-cock/anti-brake, burst mode, and even with standard Jing Gong G36 gears it fires faster than the mag can keep  up.  I'm actually minded to use the rate of fire reduction to dial it down a bit.

You can spend more on optical mosfets and messing around with the gears, but it seems that a half decent motor, driven hard enough, is all that you really need to get near-wankegun performance.

 

[Colin Allen]

I agree with Rogerborg; you don't need one of the in-gearbox units.  A decent mosfet, such as the Perun AB++ or, if you do not want pre-cocking, a Gate NanoAAB, will do the job.

Changing the gears to 16:1 will give a slight additional improvement but a new motor, a higher voltage battery, a mosfet and Deans will probably be enough.

 

[Tactical Pith Helmet]

Changing more than one component at a time makes problem solving extremely difficult. 

Mosfet fitted - test.  Motor changed - test again.  Add 11.1 and test. 

If you want more development after that, it's exponentially more work.  

 

[MrTea]

Thanks for the input, especially on the MOSFET side of things. I've shot an email to a local tech/store who just so happen to stock both of the MOSFETs you mentioned. I've detailed that I would like the original battery connections swapping to deans and fuse removing if possible so i'll see what they come back with. Soldering & mosfet installs are over my head.

I only intended on changing the gears because the ones in the gun must be stock and are already showing signs of wear. Might as well change them given how inexpensive a new set is.

@Tactical Pith Helmet I did intend to install everything sequentially for this very reason in case I buggered anything up.

 

[Pollynator_bravo2]

Changing more than one component at a time makes problem solving extremely difficult. 

Mosfet fitted - test.  Motor changed - test again.  Add 11.1 and test. 

If you want more development after that, it's exponentially more work.  

I totally agree with this from first hand experience. It took me three months to get my build functioning after over modding and not being able to find the loss in fps and inconsistent firing. Turned out to be something super simple in the end