The Johnson had some interesting features – primarily its magazine design. It used a fixed 10-round rotary magazine, which could be fed by 5-round standard stripper clips or loose individual cartridges. It could also be topped up without interfering with the rifle’s action, unlike the M1. On the other hand, it was not well suited to using a bayonet, since the extra weight on the barrel was liable to cause reliability problems (since the recoil action has to be balanced for a specific reciprocating mass). Johnson thought bayonets were mostly useless, but the Army used the issue as a rationale to dismiss the Johnson from consideration.

[17:56] https://youtu.be/aY19tDMDvr4?si=