The Better Box Magazine

[Gigueand]

Hi guys,

I just picked up a CA M249 with a MAG push-button winding 100 round "nut sack."
 

I'm finding that in order to feed the gun I need to basically hold down the wind push-button the entire time I'm firing. Is this normal? 

 

Having never owned a SAW, I assumed that the box magazine would function similarly to a standard hi-cap, but that doesn't appear to be the case.

 

Are there any M249 box magazines that don't require a push-button? Obviously, the sound activated ones are available, but they don't seem entirely reliable to me and are also large in size compared to the "nut sack." 

 

Basically I'm wondering if there are any other box magazine options available that can be wound up and forgotten about.

[Imperator]

I'm not an expert in airsoft LMG's, never having owned one, but I do believe there is another box mag version, other than sound or push-button activated.
It feeds the bb's by being electrically connected to the gun trigger contacts. So, every time you squeeze the trigger, the box mag feeds.
I'm not sure, but I believe this may be a DIY mod.

[Deve]

STAR's M249s worked like that, pulling the trigger both operated a microswitch to the gearbox and completed the box mag circuit, so it auto-wound when you fired.

 

The G&P Stoner 63 is similar, if a bit more complicated, in that when the trigger is pulled, the circuit is also completed to a relay in the box mag switch starts the motor winding (based off a separate box mag battery) and keeps winding for a few seconds after the trigger is released.

[PMO Gordo]

Here's the DIY mod for making M249 box mag wing in sync with trigger pull:

. Although I would add a pair of dean connectors between the mag and the gearbox for ease of swapping out the magazine. Also, some LMGs come with the feature out of the factory, such as the ARES LMGS.

[ED-SKaR]

The magazine *should* function like a normal hicap magazine that builds spring tension whilst winding then uses that when firing. You should get a minimum of ~200 rounds from it before it starts misfeeding, usually 300-400.

 

Auto winding mags can be set up in a multitude of ways. Most of the guns I work on the owners ask for the motor of the box mag to be wired directly into the main current to the gun. IE whenever you pull the trigger, the boxmag winds too.

This is the most reliable and simplest to operate in the field.

 

I personally prefer push button on the magazine, as then you can detach the magazine without having to pull out a deans connector. I have not used a support gun though, only a rifle with a larger magazine than normal (500-100 rounds rather than the 1000-5000 of a lmg)

[kojak]

The somewhat rare CA 100rd "nutsack" mag has a reliable automatic mode (triggered by tension I think), and an easier to access top reload hatch. 

 

I usually use a MAG (modded with a top refill under the fake rounds) for its almost double capacity; I mount the pressure switch above the trigger on my SAWs and fire with my middle finger: 

 

[Gigueand]

Thanks, guys.

 

I'm going to put the SAW through its paces this weekend. I'm bringing the box magazine along for a test run. I'm also borrowing a few high caps if running the box magazine proves troublesome.

 

I like how you've got your push button set up, Kojak. I may try something similar. I'm thinking a piece of velcro on the receiver and a piece on the button.

 

Another question while I've got you all here:

 

For those with the Mk46 stock, do you (can you?) run a battery inside the buffer tube? I've the standard full-stock on mine, running the battery in it, but the LoP is a bit long for me.

[kojak]

You could, but I wouldn't--the battery would be too small for a SAW.  I have the biggest 3 cell lipo I could squeeze up front, and still run out of juice occasionally.  It's a pain to swap in the field since the barrel has to come out, so I sometimes ziptie a spare under the top RIS if I'm not too concerned about looks:  

 

  

 

I have tubing over the feed spring to keep dirt and debris out.  You can fit a pretty big battery in the dead space of the A&K sound control box mag, but for me it isn't worth the bulk.  

 

Here's the fast reload mod for the MAG box: 

 

 

I made a "sled" out of thick Kydex that snaps under the feed lips, then cut out a nice big opening in the plastic underneath.  Not only is this much faster and easier, but you can really fill it up to the brim.  

[Gigueand]

Nice!

 

Thanks!

[PMO Gordo]

If I own a M249, I'd probably rewire the box mag, so that it houses a large LIPO battery which powers both the gun and the winding mechanism. Below is the instruction on how to put large LIPO battery in the box mag: http://www.scalerocketry.com/m249boxmag/m249boxmag.html