LeCoultre used BW sub-designation on some movements, just not the 450. Nevertheless, I suspect some feature of the LeCoultre base calibre is the origin. Perhaps a watchmaker that has disassembled these would know.
Paying attention to the history of vintage V&C, there was a movement that must say: caliber 453. Ebauches JLC caliber 450, 12.75 ''' I have seen the following generations in the family: 1. 453C1 2. 453/2C 3. 453 4. 453/3C 5. 453/3B 6. 453/3BW After search...
I believe the B marked VC movements were their best manual movements. As far as your more detailed questions, I'll bet Tick Talk will be able to help you.
I have never seen an official explanation for these designations so if anyone has documentation it would be wonderful. Comparing the movements pictured, that "W" resulted in many visible differences from the /3B. Kif-flector, 18 jewels, adjusted to temper...
LeCoultre used BW sub-designation on some movements, just not the 450. Nevertheless, I suspect some feature of the LeCoultre base calibre is the origin. Perhaps a watchmaker that has disassembled these would know.
The first version had no writing indicating the number of jewels/adjustments. Just the serial number, and the V&C logo. The second was fully marked, but the reference number had no letter behind it. Also, at this time, import codes were being introduc...