I think he is well beyond building weapons that are fired by gun powder.
https://machindustries.com/articles
But offering neither, your thread title was, in effect, click-bait.
In the end, it wasn't a rifle and it was never so much as test fired.
So the links you offer were little more than disinformation utterly irrelevant to this topic.
If you're truly posting for the benefit of your fellow Freepers and not for personal aggrandizement, AND YOU'RE LINKING TO A FOUR_HOUR VIDEO, you shouldn't leave it to the readers to do the deep digging. If the title offers a gun (or a hot new car, or a rare Rickenbacker guitar, yadda, yadda, yadda), pictures are essential, especially if you're linking to a video. In this case you didn't even bother to note the time on the video with the relevant passage.
That's not doing your best for your fellow Freepers.