Original U.S. WWII Sperry S-1 Bombsight in Steel Transit Case - Unissued British Holsters and then had additional Crown

and then had additional Crown / V proofs added on the barrel and chamber

The cylinder is also only 35mm long

BUT we do not know for which it was designed

For the United States

The tradition of exception baseball teams in the U

Original U.S. WWII Sperry S-1 Bombsight in Steel Transit Case - Unissued British Holsters and then had additional CrownOriginal Item: Only One Available. Manufactured by the International Business Machines (IBM) the Sperry S 1 bombsight was designed by Elmer Sperry, Carl Norden's former employer. It had several distinctions from the Norden, and some advantages. The Sperry gyroscopes spun at 24,000 rpm, compared to the Norden gyros which ran at approximately 8,000 rpm. This higher rate of rotation overcame the tendency to precess, so there was no leveling mechanism