Henry had approximately 5,000 archers at Agincourt, and a stock of about 400,000 arrows. Each archer could shoot about ten arrows a minute, so the army only had enough ammunition for about eight minutes of shooting at maximum fire power. However, this fire power would have been devastating. Fifty thousand arrows a minute – over 800 a second – would have hissed down on the French cavalry, killing hundreds of men a minute and wounding many more. The function of a company of medieval archers seems to have been equivalent to that of a machine-gunner, so in modern terms we can imagine Agincourt as a battle between old-fashioned cavalry, supported by a few snipers (crossbow-men) on the French side, against a much smaller army equipped with machine guns. Perhaps from this point of view the most remarkable fact about the battle is that the French ignored the very great military advantages of the longbow.

Read the article here. Just ignore the math!