The year of manufacture for serial number 1244385 is Between 1943 and 1948..
No records are available form 1943 - 1948.
41 1238585 48883
42 1287469 29981
43 -- --
44 -- --
45 -- --
46 -- --
47 -- --
48 -- --
49 1500001 126100
As you can probably imagine, keeping separate records also creates discrepancies in establishing year of production of some guns, up to several years in some cases.