TFB is showing off a sketch that a reader sent in which I think is a very innovative idea. Its a pistol caliber upper…. that would work on any standard AR lower. Thus eliminating the need for a dedicated lower or a lower conversion. Seems like a very simple idea too.
If it works, it would make the cost of running a pistol caliber AR a little less prohibitive. I like it… and would be one of the first to buy one if it works.