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swatti

Custom LMG / Boxmag feed system - who wants one?

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It seems no matter what brand or model one thing is universal. All boxmags feed terribad and suck. Aftermarket solutions are far and few with most just being the same thing copied over and over again with the same faults and issues sometimes even worsened.

"I'm here to change that"

This started out as a quest to make a "remote feeder" for a HPA pistol. Introduced the idea to some people and many came asking for a feeder to their LMG, and from there it evolved...

Long story short, I 3D model stuff and 3D print stuff. So, I modeled a feeding-system, based on a system in a gun from nearly 30 years ago and referred by many as one of the most horrible guns to work on, ever... The TOP M60. AEG LMG without an actual gearbox. Let that sink in for a while.

To the point. That gun "direct feeds" as there is no "hi-cap" inside or  even an actual magazine, you just open the top-cover and pour the BBs in. Gravity feeds them the intake and from the the axle of the motor runs a geared "wheel" that feeds the BBs in to the gun. Its actually not as simple as it sounds. But it could be. 

First issue for many LMGs is that the feeder is too weak. Almost all rely on regular "hi-caps" that weak motors wind thru several gears. Next is the "vertical" mounting of the units such as the basic M249 big-box where the feeder takes 2/3 of the space and last but not least, the jamming. Mostly due to all other of forementioned.

How to fix the universe? I'm with Thanos on this one but how to fix the magazine takes a few steps.

One is horizontal mounting. TOP M60 did it first, but many are more familiar with the MAG M249 "small box" magazine. The winding wheel is in the bottom "floor" of the magazine leaving lots of space and area where the BBs fall into the feed-wheel. 

Second is moar powah! A proper 12v, or in our case a 11.1v lipo run system. This is where the MAG failed as they, and many others use RC servos. They are very slow, even the faster ones and quite brittle if not
metal-geared. Bigger servo is just wasted space and properly geared the price jumps. They ar not "meant" to be driven long times.

 

Third is the hi-cap spring. It has its perks but lot of issues too. They need a "delayer" or the spring reverses when over-spinning on empty and snaps soon after. The springs decay over time and are quite weak to begin with. Also, bloody cuts on fingers when they get loose.

My system combines all 3 fixes. Its a horizontal mounted unit with plenty of space, its driven by geared 12v motor and has no winding spring.

"So, how does it have tension to feed first BBs?"
If your gun has its piston already "at the back" and ready to, the BB has already been chambered. If not, the magazine will have enough time to run the chamber-cycle before the shot. Obviously the magazine will need to run as you shoot. The feeding tube "spring" most guns use also stretches a tiny bit. Thats enough tension to chamber 2-4 BBs without winding the unit.

"What about over-feeding?" 
Where the winding-spring used to be now houses a mechanism similar to the original spring when it starts to "skip" fully winded. This just starts to skip at when the winding wheel can no longer spin. My rallye-driver english fails me here, I don't know the proper term for it. The torque it can take can be adjusted fairly easy if needed.

 3D printed and designed to fit the original M249 magazine. Most "box mags" are not much smaller than that. Some drums might not fit this but I would say AK drums could. 

The base-plate can be sized up to a size of the bottom of any magazine if I just had the correct numbers. Till then its gonna need some tinkering or give me some numbers.
This particular unit is not very well suited for the original remote pistol-feeder but it has been built with the idea of a backpack or "murderbox" in mind. The metal spring used to feed rounds thru starts to make lot of friction once it gets 50cm+ and then the winding spring simply isnt enough to push the BBs thru. PTFE hose can help, but only a bit as the BBs really do start to have considorable weight. 
This fella can feed "over the shoulder" from a backpack.

The light blue part is the output for the BBs. Its meant to fit the feed-spring but if need be I can increase the bore to fit a 9mm OD, 7mm ID size PTFE tube for those murderboxes. Connectors to and from the hose or spring can be made easily of need be.

There are 3 operational units built and all tested. What I need now is some quinea pigs to test these in the field. 

Anyone? 😉

What I need from you is some DIY skills to modify this into an existing magazine, OR measurements of your magazine. Most likely it will need some dremel-work still. If possible, access to a 3D printer incase parts need to be re-made or altered.

Price will be 50€ + shipping. 
Shipping to US was 15€ so around that is to be expected.

I'l upload some videos later...

RfOpPRg.jpg

EDIT1: Pic posted. 
Ordered some more motors. ETA... Umm... Well, roughly couple weeks. Maybe.

 

Edited by swatti

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5 hours ago, J-man said:

If you could get these to fit into a M240 Contact mag. Myself, and a few others would be interested.

 

Can you pass me a picture of the original feed system and the boxmag when empty?

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