4500 .50 Beowulf 10 .50 Beowulf Magazine, 10 A conversion of the standard 30 round NATO 5.56 magazine to take 10 rounds of the high-powered .50 Beowulf ammunition. .50 Beowulf 10 Alexander Arms' 10 rounds magazine of FMJ.50 Beowulf ammunition. 1024 387 1 747 3 4 20 180 5 1 1 1 6 -10 2 6 387 38 10 2