The Remington Model 721 chambered in .30-06 was produced between 1948 and 1962. To determine the specific date of manufacture for serial number 286537, you would typically need to consult Remington's records or a reference guide that correlates serial numbers to production years. Generally, serial numbers in the 286,000 range suggest it was made in the late 1950s. For precise dating, reaching out to Remington or a firearms historian would provide the most accurate information.
Depends on the model.
Remington Works - 1914 (late)
your Remington model 6 was made in 1998,due to the S prefix on the serial#.
1912
1920
1924
1912
1912
1923
1914
1911
1917