Serial Number Ranges

Year

Colt 1924-1945

1924 700001-710000
1937 710001-712349
1938 712350-713645
1939 713646-717281
1940 717282-721977
1941 721978-756733
1942 756734-793657
1942-USN 793658-797639
1942 797640-800000
1942 801001-856100
1942-43 856101-958100         (1943: ~862000-958100)
1943 1088726-1092896
1943-44 1096405-1208673   (1944: ~1155000-1208673)
1944-45 1609529-1743846   (1945: ~1720000-1743846)
1945 2244804-2368781   (Last pistol by Colt)

Year

Ithaca Gun Co. 1943-1945

1943 856405-916404
1943-44 1208674-1279673     (1944:~1235000-1279673)
1944 1441431-1471430
1944-45 1816642-1890503    (see Ithaca shipping records)
1944-45 2075104-2134403     (1945: 2110465-2134403)
1945 2619014-2660318     (last pistol)
Year Remington Rand, Inc. 1942-1945
1942-43 916405-1041404        (1943:~921675-1041404)
1943-44 1279699-1441430      (1944:~1363700-1441430)
1944 1471431-1609528
1944 1743847-1816641
1944-45 1890504-2075103      (1945:~2031550-2075103)
1945 2134404-2244803
1945 2380014-2465139     (last pistol)

Year

Union Switch & Signal 1943

1943

1041405-1096404       (55,000 total production)

The preceding information was obtained from "Colt .45 Service Pistols Models of 1911 and 1911A1", by Charles W. Clawson.