A standard magazine can hold from 40 all the way up to 80 BBs. However Tokyo-Marui has also manufactured high-capacity magazines which are known as Hi-caps. These magazines can hold anywhere from 200 to 600 rounds of BB pellets. Half of the magazine is used purely to hold the BBs while a wheel at the bottom of the magazine is manually rotated to draw BBs up into the "ready" tube. BBs in the ready tube will be drawn into the gun when fired. Usually a Hi-cap will make more noise when you move around because the BBs inside will bounce around and the user will need to spin the wheel occasionally to ensure enough BBs are drawn up to be fired. Standard magazines by comparison hold alot less and you may need 2 or 3 to last you through a game but they make no noise. For the cost conscious or airsoft player who doesn't like reloading the hi-cap magazine is the definitive choice.