Drum magazines store rounds in a spiral or a pair of drums, giving 50 to 100 rounds in one magazine. They are fun at the range and heavy on the rifle. Expect slower loading and more weight than a box magazine.
High-capacity box alternatives
The Surefire 60 and 100 round magazines use a four-column box instead of a drum. They are lighter and fit standard AR15 pouches better than most drums.
