what is the manufacture date of a .38 police positive special serial number b 81
You did not provide a serial number.
Impossible to answer without the serial number.
about 1936 (I believe)
You can find out at Proofhouse.com
@ 1969
1980
@1977
1977.
Impossible to answer without the serial number. You will have to call S&W
A Colt official police with that serial number was made in 1948.
Colt police positive special with that serial number was made in late 1922.