Hello everyone! I recently acquired a boneyard Thompson SMG on the cheap to fix up and realized something. Due to the way the magazine is inserted into the gun, it would be a relatively simple task to create a magazine conversion kit to allow M4 magazines to be used. As soon as I thought of this abomination, I knew I had to create it. Since I own my own 3D printer, I can actually produce this. I have printed a low-resolution low-infill prototype to test the fit of my rough mock-up, and it almost worked. I have since revised the design and ordered more filament. I will attach photos of the finished result once I have it printed successfully. The reason I am posting this thread is because I wanted to see what the airsofting community thinks of this unforgivable sin. Disclaimer: If you couldn't tell by the tone of the above post, I am fully aware there is no way a conversion kit like this would work in real life. There is no way a 5.56 round could ever feed into a .45 caliber SMG. That being said, I still fully intend on using this at some point, as m4 mags are a fair degree cheaper and more readily available for purchase.