| The caliber 3157 [message #2065] |
Fri, 01 November 2013 12:46 |
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Thojil
Messages: 650
Registered: May 2013
Location: Concorès, France
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Gruen Master |
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Caliber 3157 is a 17-jewel movement and is 10-1/2 ligne or 23.69mm in diameter. More frequently seen is the 15-jewel version, called 315. Production start of the 315 was 1929 and the 3157 followed in 1930 (Barry C. & Mike B. dating table). Unknown if this movement was actually produced by Gruen?
Three other variants exist; calibers 344, 345 & 347 (7j, 15j & 17j). These were introduced between 1934 and 1935. No information is is known to me as to what the differences were versus the 315/3157.
[Updated on: Fri, 01 November 2013 17:45] Report message to a moderator |
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