I’m interested in helping research towards making higher-caliber weapons possible with fully DIY components. I’m still not that well versed in weapon design and I know many people here have more experience with converting components so the main thing I’d like to know is what limitations need to be overcome?
I have an idea for the ECM taper that may work but it’s yet to be tested. The other complexity is the bolt carrier group and the locking mechanism but I think that can be made with guides. The other consideration is the gas system, a section could be attached to the gas port without welding with a clamp but then I’m not sure if direct impingement or a piston system is the way to go.
Any help is appreciated.


Just boils down to figuring out locking geometry, yeah
Trying to think of a simpler mechanism than rotating bolt lugs. The lugs on a typical assembly could be made from a steel part with a rim on one side and filed down using a guide and then drilled through the middle for the firing pin. The main issue I think is the complexity of the bolt internals. It may be possible to FDM some of the internals that don’t take the brunt of the stress (maybe in a CF polymer) though again it may just explode.
If not using direct impingement the bolt can be simpler however it would still take many drill guides. The extractor and the breech face lock itself seem difficult to make unless they are changed.
I suppose if a barrel with taper could be successfully made with ECM then the breech face could be as well with the same principles? Maybe with 6 wires just inserted into the end so that it creates the pieces to lock into. I definitely need to do lots of experimentation so see if all of these ideas are possible.