Jump to content

Ready-made M249 MOSFET


ardrummer292

Recommended Posts

Hello again! I'm still working on building up my new Classic Army M249, with the desired end-state being maximum durability and minimum maintenance. I believe the gun is entirely stock, so I plan on running it until it breaks. I have quite a few parts on hand I plan on using as replacements, with a few others I still need to purchase. As such, I've got a bit of a shopping list for replacement parts:

 

 

 

External:

- Real M249 bipod*

- Real M249 carry handle assembly*

 

Gearbox:

- SHS torque gears*

- Some form of full metal tooth piston*

- Alu piston head*

- SHS torque up motor

- Metal air nozzle

 

Barrel and hopup:

- Bullgear M249 hop unit (if feeding problems arise from hopup unit rotation within the receiver)

- Bic pen mod hopup nub*

- Guarder clear hopup rubber

 

Electrical:

- Upgraded 20A microswitch

- Some form of pre-made MOSFET?

 

*: denotes an item already owned or purchased

 

 

 

The pre-made MOSFET is a bit of an issue, as I can't seem to find anything like that. I'm awful with electronics and wiring, so I certainly don't feel capable of manufacturing one myself. I honestly don't even know how to solder, so I'll have to pawn off any intricate work like that to a friend.

 

I found something that might work on Evike, listed here:

http://www.evike.com/products/34840/

While it seems to do the job of a MOSFET, I have no idea where I would mount the relay switch box itself. After contacting Evike tech support, the rep told me that I would have to make some sort of "custom accommodations" for it somewhere in the receiver or grip. It sounds like removing the gearbox would be significantly more difficult if that's the case.

 

Sorry if this post doesn't make much sense. I'm a bit lost when it comes to the magic known as "electricity." I deal strictly in the mechanical realm. If anyone would be willing to help, please do. :)

Link to post
Share on other sites

With the Evike wire set, I don't think you will get any performance increases as you would with a MOSFET, just durability.  Wiring in a MOSFET should be like any other AEG; the box mag can just be wired in parallel with it if that's what you're worried about.  That's what I did with my PKM and those are even more complicated.  

If you do go with that wire set, I don't see why you can't mount the relay to the top of the gearbox using some sticky velcro.  

Link to post
Share on other sites

Thanks for the reply! I'm not concerned about performance, only longevity. I also ordered 2 of the CA 1200rd "nutsack" box mags, so I'm not terribly worried about modifying the wiring to trigger the box mag. It sounds like the Evike product might work after all.

I can't tell if it would work with a front-wired M249. Any ideas?

Link to post
Share on other sites

I forgot if front wired 249s have their batteries in the box mag or under the barrel, but in either case, it should be easy to make a wire extension.  Also, forgot to mention this, but the wire set has some pretty thin wiring, like a stock ACM gun, but just prettier, so you might want to reconsider.  

Link to post
Share on other sites

A better switch will last a bit longer than stock, but if you're using higher voltages it will eventually fail.  My personal SAW (1.6J, 32g BBs, 11.1V lipo) went through several pistons, sets of gears and a couple cheap MOSFETs before I got it sorted.  

 

I use an Infected Armory AB FET, clear blue SHS piston with full steel teeth (AOE corrected), and meticulously shimmed SHS helical gears.  Haven't done anything to it in two years besides clean the barrel.  

Link to post
Share on other sites
  • 6 months later...

I ordered the Angel Custom M249 relay switch assembly from Evike. The wire used to connect the battery to the motor seems to be very heavy gauge, probably about 12-14. Installation in the gun is very straightforward, no soldering required. Fitting all the components in a front wired gun, however, is a beast of a task. I did eventually manage to cram the relay switch, wires, and a very flat 7.4V LiPO under the barrel with minimal interference. Zipties were extensively used to ensure that nothing popped out of place.

 

The relay switch performed admirably up until a couple weeks ago. After some troubleshooting, I determined that the internals of the relay switch were getting jammed, causing the gun not to fire when the trigger was pulled.. After whacking it a couple times, the jammed relay switch component broke free and the gearbox functioned correctly again. A simple fix, but not exactly confidence inspiring stuff.

 

I have since scrounged another gearbox with a MOSFET installed, which performed well for all 45-50k rounds I put through it this past weekend.

Link to post
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use and the use of session cookies.