The BAR should not be considered a light machine gun, such as the Bren or the Breda 30 or the Degtyarov, but rather an automatic shoulder weapon, a flexible infantry arm only a half-step above the M1. I believe Browning intended it to be this kind of arm.
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It fires from an open bolt and its strong spring jolts the gun enough to make accuracy rather a matter of hope than holding. Beyond 200 yards the BAR is mainly valuable as a harassing weapon; up to 200 it can really mow things down, in the hands of a good man. That is important, too; I think it takes longer to make a good BARman than a good rifleman. He needs plenty of practice with live ammunition.
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One thing sure, if a man has any tendency to flinch, a Browning will intensify it. It took me two years to get used to shooting BARs, but I finally was able to master them, being able to completely control them.
There were times when real machine guns paid off:
Too, there were times in the early Pacific warfare when watercooled .30s paid dividends, but after the Nips woke up to the fact that nine out of 10 of their banzai charges ended with them running out of soldiers, business was not so booming.
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For aircraft use, the faster a gun fires, the better.
Clyde Barrow’s weapon of choice