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.
I think expectations need to be maintained when making higher caliber weapons. I think what would count as “DIY’able” to me is for the gun to be made in Europe with no special equipment or custom parts, only with FDM, standard tools and common metal parts (except the barrel). Without welding is ideal but not necessarily a requirement.
Delayed blowback does not really solve the problem because it wouldn’t work for stronger rounds (or it would likely be unsafe). For a piston system (for example) a steel block could be used, then one hole drilled that connects to the gas port hole and then one larger drilled hole containing the hammer system. The hammer used could be a common metal part that simply fits the diameter of the drilled section.
It would help if you define what you mean by “higher caliber”. The French AA-52 was a lever delayed 7.62x51 and the Soviet Garanin was a lever delayed 7.62x54R. The French MAC-58 was a lever delayed 50 BMG! And of course the H&K G3 in 7.62x51 was a roller-delayed blowback system.
If you do the math you’ll see delayed blowback is every bit as viable as gas systems for pretty much any caliber. Gas systems are more prevalent now simply because they’re cheaper to produce, have higher tolerance for harsh environments, and tend to have longer service life, but neither of those are really priorities for privately manufactured firearms for civilian use.
It does seem like an interesting route. Only thing is that it seems like it would put a lot more force on the receiver from the accelerator lever so a metal element would probably have to be inserted in the section of contact. I think my concern with that is that it would put a lot of stress on a polymer receiver, yes there are examples of higher caliber weapons in production with a blowback system but if the receiver is less strong then it could put too much stress on weaker components and it could be a safety concern. I’m still learning but this is my view right now.
By higher caliber I mean higher than current hybrids (9mm) so 5.56/300blk and 7.62x51.