New Army "Caliber Configuration Study"

[stanc]

In the context of the ongoing discussion, the BAR was employed as the SAW/IAR of its time, while the M1919 was employed the M240G of its time; hence the terms used are relevant to the discussion.

If you look at the criteria I posted earlier of Light v Medium v Heavy, they also fit the parameters. I will add some additional criteria that I think should be fairly widely accepted;

Light – Employed by single person (BAR, SAW, IAR)
Medium – Employed by a team (M1919, M60, M240G)
Heavy – Employed by a team, but due to system/ammo weight/bulk, normally fixed or vehicle mounted (M2, M1917, Mk19)

The problem is you are placing some weapons in categories that are technically incorrect. Neither the M1918 BAR nor the M27 IAR are properly classified as light machine guns. And while the M1919 LMG could reasonably be thought of as the M240 of it's day, the M1919 was not then considered a MMG.

It'd be like calling the M1896 Krag carbine a rifle because it has a 22" barrel, longer than those of many modern military rifles.

To avoid such contradictions, I'd suggest leaving historical weapons with their original classifications, which were appropriate for their times. That's if there's even a need to include them in the discussion.

I'd also suggest that four categories are needed:

IAR
LMG
MMG
HMG