Update 13/07/26: Added wmp5_Barrel_PropTop.stl to the parts list. I got a request for an alternate barrel top without the wiimote holding section. 
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An absolute classic!

I'm tempted to do the little stubby MP5K too

The suppressor absolutely blocks the wiimote sensor, so you will have to unscrew it in use.
I included the fisheye lens thread in case you need it but its optional, not a requirement.
You will need a small rubber band or pen spring for the trigger return.
I got carried away with the magazines, so there are four to choose from.
The hollow area in the Bstock_Back is for you to fill it with heavy things as a counter weight to the wiimote.
Added Nunchuk (holder) & Barrel_Bottom_rail parts, I think you will work out what they are for.

I printed mine with a 5% Rectilinear infill with basic pla. You might want a brim on the Bolts, Mags, Supp & Nunchuck (holder). I might try and make the suppressor lighter, maybe reduce the length of the inner barrel wall as its weight does strain on the bolt-like connection.

Eyes on target!

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