 Despite new U.S. contracts for Lend-Lease shipments abroad to China, France, and the United Kingdom, as well as the needs of American armed forces, only two factories supplied M1928A1 Thompsons during the early years of World War II.Though it could use both the 50-round drum and the 20- or 30-round box magazines, active service favored the box magazines as the drums were more prone to jamming, rattled when moving, and were too heavy and bulky on long patrols.562,511 were made.