I just talked to my son, who is going through the police academy. They did range week this week and he tells me his thumb is sore from loading magazines. His class of 25 went through 7000 rounds of ammo yesterday. That's only 280 rounds of ammo each. They need to pick up the pace. When I went through my course, we were shooting 500 rounds per day.
Still, that ain't bad for a day's shooting.