I'm pretty certain Bausch and Lomb did NOT ever make the M49 - but they did make their own spotting scope with almost identical specifications - the M48, know in Civilian life as the "NRA Model". Before the end of WWII the M49 superceeded the M48 as the standard spotting scope, and was in use as a standard issue item until very recently. (Anyone here know when the M49 was replaced?)
When WWII started, as usual, the United States was caught somewhat unprepared. There was a sudden need for Spotting Scopes, for Artillery, Snipers, Forward Observers, etc.
The US Government supposedly bought up all the "off the shelf" supplies of Bausch and Lomb's "NRA Model" and redesignated it the "M4", later changed to the "M48". At the same time, the Argus built 55MM scope was also made a standard item of issue, with the new designation of "M49", and I would assume civilian stocks would have probably also been acquired, if available.
US Contracted items are frequently produced by multiple makers - both to increase supply and diversify sources in case one is compromised. I'm sure someone here knows more about the M49 than I - I specialize in the B&L scopes as a very new, neophyte collector........ CC
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