“Will all vintage WW 2 Elgin A-11 watches have 539 16 jewel or could one be a 685 movement 18 jewel? ”
Your email states the 539 vs 685
.
Well here is one with “ELGIN 532”
Thus the 500 series = WWII
Then we have the Korean War
1950-1953 KOREAN WAR
during 1950’s ELGIN PRODUCED THE 6OO SERIES
Elgin 685
Elgin 680
Elgin 681
Elgin 682
Elgin 683
ONLY THE 1951-54 685 WAS A HACKING MILITARY MOVEMENT
AND WERE MADE FOR PILOT AND GROUND POUNDERS
IN FACT, SOME WERE PRODUCED WITH 24 HR DIALS
685 MOVEMENT
Elgin 685
Features
manual wind
sweep second
option: hack feature
option: 24h display
the key is DOES IT HACK.
WHEN YOU PULL THE CROWN “DOES THE CENTER SWEEP HAND STOP” AND WHEN YOU PUSH BACK IN “DOES IT START”?
on one of our 9 sites i have actual specs :
ROCK
US ARMY SPECIFICATION NO. 94-27834-B
Dated FEBRUARY 22, 1943 –
WATCH, NAVIGATION, TYPE A-11 (HACK):
F. METHOD OF INSPECTION AND TESTS: F-5. Individual Tests.- Each
watch shall be subject to the following tests: F-5a. Room Temperature Rate
Test –Horizontal Position. – The watch shall be fully wound and run for one
day to allow it to settle down. The daily rate of the watch then shall be
determined for a period of 3 Consecutive days with the watch in a horizontal
position with the dial up and with a daily winding.
The average of the daily rates during the test period shall not exceed
30 seconds. F-5b. Room Temperature Rate Test – Vertical Position. –
The daily rate of the watch shall be determined for a period of 3 consecutive
days with the watch in a vertical position, with the pendant down and with
daily winding. The average of the daily rates during the test period shall
not exceed 30 seconds. The difference between the average daily rate
obtained in this test, and in the test specified in Paragraph F-5a, shall
not exceed 45 seconds. F-6.
Routine Type Test. – The following tests, in addition to those specified
in Paragraph F-5,shall be applied to not less than 5 watches selected
at random from each hundred or fraction thereof that are contracted
for. F-6a. Plus 35 Degrees Centigrade (Plus 95 Degrees Fahrenheit)
Temperature Rate Test – Pendant Down Position.- The watch shall be
fully wound and then subjected to a temperature of plus 35 degrees Centigrade (plus 95 degrees Fahrenheit) for a period of 5 hours. During this period, the
daily rate of the watch shall not differ more than 20 seconds from the
average daily rate obtained in the test specified in Paragraph F-5b.
(In order to arrive at the correct figure for the rate allowance for
the temperature test,the error noted for the 5-hour period shall be
multiplied by 4.8 in order to determine the rate for 24 hours). F-6b.
Zero Degrees Centigrade (Plus 32 Degrees Fahrenheit)-
Temperature Rate Test – Pendant Down Position. – The watch shall be tested as described in Paragraph F-6a, except that the watch shall be at a temperature
of zero degrees Centigrade (plus 32 degrees Fahrenheit). The daily rate of the watch shall not differ more than 40 seconds from the daily rate obtained in test specified in Paragraph F-5b. F-6c.
Waterproof Test. – The watch shall be suspended above a beaker of water
placed in a vacuum chamber which shall be evacuated to 5 1/2 inches
of mercury (to simulate a condition of 72 inches of water), then the watch
shall be immersed for a period of 15 seconds. There shall be no evidence of
leakage of water into the watch during the test period. Leakage will appear as bubbles emanating from the back, crystal, or stem of the watch.