The BAR gets a lot of criticism as a poor performer in the "light machine gun" role when it was never intended to take the place of light machine guns per U.S. Army doctrine, although subjective criticisms of the weapon in the role it was placed do exist.

As I wrote here, the absence of full-power machine guns from American rifle squads was primarily due to the doctrine of fire and movement; the most basic elements had to be mobile in order to accomplish their assigned mission of closing with the enemy and destroying him. Light machine guns, as a result, were placed above rifle squad level.

I wrote about the evolution of the U.S. Army rifle squad from 1938 to 1944 here.

The Browning Automatic Rifle was operated in the same vein as a light machine gun, with a team of several men;

Men:

Quantity	SSN	Rank	Role
1b	746	Pvt./Pfc.	Rifleman, automatic
1r	746	Pvt./Pfc.	Rifleman, automatic, assistant
1r	746	Pvt./Pfc.	Ammunition bearer

Equipment:

Equipment	Quantity
1	Rifle, Browning, automatic, M1918A2
2	Rifle, U.S., cal. .30 M1

• b: armed with rifle, automatic, cal. .30

• r: armed with rifle, U.S., cal. 30, M1

The Browning Automatic Rifle gunner carried and fired the weapon, along with carrying twelve magazines of ammunition in an M1937 cartridge belt. His assistant carried spare parts and oil for the gun, and was designated as the backup gunner should his superior fall. The assistant gunner and ammunition bearer were also equipped with M1937 cartridge belts for field use, but received M1923 cartridge belts for garrison use. Every member of the rifle squad had a general purpose ammunition carrying bag (capable of carrying, among other things, 10 BAR magazines), and the ammunition bearer of the BAR team got two. It was intended that the assistant gunner and ammunition bearer would use their M1937 cartridge belts to each carry an additional twelve BAR magazines, and carry their rifle ammunition or more BAR ammunition in their general purpose ammunition carrying bags. The M1937 belts of the assistant gunner and ammunition bearer were deleted per a change in the rifle company T/O&E on June 30, 1944, and the practice of keeping ammunition was nominally reversed, with the rifle ammunition in the M1923 cartridge belt becoming paramount, and any additional BAR magazines going in the ammunition bags.

The June 30 T/O&E change also authorized six unassigned BARs in the rifle company. When faced with German squads that possessed machine guns, many American units formally or informally introduced a second BAR in the rifle squads; one BAR would open fire until its magazine was empty, and the second BAR would pick up right where the first one left off, covering it while its user was reloading. As the BAR, as well as a decent quantity of ammunition, were transportable by one man, the ammunition bearer was sometimes dropped; in other cases, it became a one-man weapon. The bipod, as it added several pounds to the weight of the weapon, was also often discarded, and is not often seen in period photos.

Subjective complaints about the BAR when compared with other squad-level automatic weapons of the WWII era like the Bren or MG 34 include an inability to sustain fire for long periods of time due to a fixed barrel, and a small magazine capacity. The BAR was experimented with as an antiaircraft weapon throughout the 1920s, 1930s, and 1940s, and 40-round magazines were used in this role, but they were out of service by 1927.