Printed mine with some generic petg at 235C bed 75C
0.12 layer height with snug supports tested mine with 70% infill
print at the orientation the file is or you can test what works for you
still uses the same m3 nut and screw for the m4 conversion, use filament for the lever(might need to drill the hole bigger, could be my printer/slicer settings issue
The author remixed this model.
Made the mag release arm a bit thicker and added the hole to mount the ambidextrous magazine release and cut dannythenoob's button shorter and moved the hole for it to function fine with my design.