(Themed) Full Custom DMR Build

Discussion in 'Gun Building, Modifications & Repairs' started by brick, Nov 12, 2015.

  1. brick

    brick Member

    Hey, all.
    Having recently acquired access to CMC and 3D Printing Machinery, a few friends and I recently embarked on creating a functional, faithful replica of the M395 DMR from Halo 5.
    Now, the majority of the Externals are all going to have to be custom made using that machinery, which won't be a problem. However, neither of us have much experience with internal parts or upgrades aside from basic maintenance and tuning up, and are for the most part at a loss as to what parts to buy (i.e. Motor, Gearbox, Battery, Barrel, etc.)
    However, this wouldn't be so much of a problem if it weren't for the fact that, to be true to the design, it would have to be a *gasp* bullpup design.

    Basically, the general idea we got is to put most of the firing mechanism (gearbox, battery, etc.) in the stock, and use M4-style mags in a depressed magwell in the stock as well. Again, I apologize for my inexperience -
    So, all in all, what motor/gearbox/batteries do you guys recommend for a ~4 Foot long Bullpup Dmr, and do you have any other advice as far as internals go?

    And thanks a lot, we really appreciate anything you guys can contribute.
  2. jbwigg

    jbwigg Member

    Just from what I'm seeing, you have a good idea as far as bull pup design, but the issue I'm seeing is that from the back of the gearbox to the front of the m4 mag is a decent distance. Last resort, have a really long stock to accommodate.
    I'll help as much as I can for measurement but it would be ideal for you to have another gun right beside you so you can get an idea of where pins and space is needed so you can focus your design around the gearbox.

  3. Jeranhound

    Jeranhound Active Member

    Depending on the amount of space you have inside the gun, I'd look at the Type 1, Type 3, or Type 6 gearboxes. The Type 1 and Type 6 were made specifically to fit in bullpups and have horizontally mounted motors to reduce the amount of vertical space taken, while the Version 3 will be a bit shorter horizontally than either while still being shorter vertically than a Version 2.

    The biggest issue I can see pulling up the model of the gun is where you stick the mag. Suppose you could use a G36 hopup chamber with its little feed tube to reach down lower and use an SR-25 mag, if you want the look of carrying the appropriate .308 mags on your vest. Will be pretty close, though.
  4. brick

    brick Member

    Yeah, thanks for the Input. I was thinking about that...
    Looking at the dimensions, I'd have >1 Square foot to put the magwell, gearbox, battery and all in...
    The other option we were thinking of was the M395B, which is essentially the same thing with a longer stock..
    Anyhow thanks for the input, and we'll be posting pictures soon.
  5. brick

    brick Member

    Huh.. thanks a lot. Yeah I was looking at some AUG and FAL-style motors, but was hesitant to make a decision. Thanks again!
  6. Lefse

    Lefse Well-Known Member Supporting Member

    It will probably be less of a nightmare to build it around an existing airsoft bullpup platform. An AUG or F2000 is probably the easiest to do it with. An L85 is also an option, but they have a proprietary gearbox design and this may give you more trouble. Another option is to use an HPA system like the Wolverine. It's made to be dropped into the cylinder window in a regular gearbox shell, so I imagine it's slightly simpler to work around than the Polarstar system.

    This is doable, but It'll take a lot of work, I'd expect you guys to be working on this all winter. If you can pull it off it'll be an awesome replica.
  7. NeoAugAU-3G

    NeoAugAU-3G Active Member

    Las Vegas
    since we are thinking outside the box on this build, i would go with a p90 gearbox, swapping out the nozzle for an m4 type, and using an m4 hop up with the mp5 magwell conversion for m4s.
    magwell conversion
    p90 gearbox

    this way the gearbox is as compact as possible, and since you are building all the mounting hardware from scratch you aren't limited by sticking to one model of gun. the m4 mags feed better than p90s and would allow your idea of keeping it all in the stock.

    if you are looking for a more simple.... buy a gun gut it and drop it in a custom receiver, then i would use an aug. problem with this is that aug mags/magwells are a bit more limiting.

    all depends how much you are willing to custom build vs drop in.