DeadzManWalking Thanks, this is some really helpful advice, I think I've found a way to make a V2 fit and as I already own one I'll initially be trying with that however if it doesn't work out I'll probably switch to a V3 for the spacing and motor alignment benefits it provides. And yeah, currently I have a few Magpul hicap magazines from an old M4 but the VN style seems a lot more appropriate so I'll take a look. Thom A293 Thanks, hopefully it'll work out, (otherwise I'll be stuck without an airsoft rifle). Alignment could be an issue in this build too as if my caliper measurements aren't nigh on perfect and the prints don't come out well then stuff could start getting very wonkey very quickly. In the mean time, turns out the drawing I used in the canvas was out of scale, I measured the approximate length of the rifle only to find it was over a meter, well an AUG is only about 80cm, so something went wrong there, I've now acquired a new image for scaling and design as you can see here: Only problem is as DeadzManWalking rightly pointed out, the motor is cutting it VERY close, and this is still a meter long, so I'll have to modify the stock design a little from the artwork but other than that it all lines up fairly nicely, so the next step it to get a mosfet unit, a battery and a new trigger mechanism and get that modelled into the file, then we can get measurements of cables and lengths so we can cut channels in for cables to run and some for metal supports to sit in. In addition I need to figure out how to mount a ris rail to a 3D printed part (securely) so that's going to require a bit of thought, then there's the consideration of weighting, ideally a rifle should have a centre of mass located around the handle of the rifle (I think, if I'm wrong someone please tell me ). So as this is going to be a very back heavy rifle (with the large chunk of metal that the gearbox and motor are in the back) we'll have to counterbalance it, IE. the battery will probably be situated towards the front of the rifle and we may even add in additional weights to improve the feel of the rifle. And because I'm growing more and more attached to that scope style I'm looking into how holosights function to see if we can't modify one a little.