Looking good. What hardware have you included in the design? Just cut sheet metal and an ECM barrel? Very much appreciate a new fully DIY design.

Took me a bit to get running, but looks great. The new features sound great as well. Since everyone might not have python and C++ build tools on their device, would it be possible to release a compiled/standalone version to make it a bit more accessible?

Are there particular print settings you recommend tweaking for smoother magazine channels? Or just overall better calibration? For context, I’m working on ironing out magazine function on the extended mags in the MP22k build with the hardware from your kit.

Looks crisp, nice color choices. Is a heavier spring usually the best solution for a binding mag?

I suppose I can’t speak out of practical experience but I do have some insight. For one, originally black power was made with what was called saltpeter, known now as potassium nitrate. That would be the “default” recipe. The other nitrates can be used but will likely significantly affect the burn rate of the powder. If you want to look into it, start with the standard potentials of each nitrate. Higher standard potential, stronger oxidizer, faster burn, more chamber pressure.

I haven’t but I’ll try when I get a chance. Honestly, I didnt really have much issue with the build, aside from casting the bolt weight which was a bit of a pain. Really just down to getting reliable ejection and smoother magazine feeding.

That seems really odd, are you sure that your bolt weight is fully seated into the recess in the bolt? I had no issues with bolt travel without touching the length of the recoil spring.

Since you have links on your BOMs to individual parts, do you recommend any builds that don’t necessarily need any custom parts? Or at least can be worked around with scrap metal, a file, and time?