If you think about the probes we sent to Jupiter and Saturn, we really are getting better at this sort of thing. The real problem is payload. If you...
I knocked out the roll pin and removed the bolt catch. Then I took a small file and ran it along the perimeter of the pin/sping hole until the peened...
I haven’t looked at the drawings in a while, but I think I remember it being pretty much a necked .308, so you’d be able to make cases and load them...