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The only way to find out how old a Bretta automatic pistol with the serial number 605222 is to call the company. There is not a listing for Bretta's by serial numbers online.
Frame
about 1917
what's the question ???
Made in 1981
what model pistol ????
1922
about 1919
about 1920
made about 1923
about 1936
@ 1972