Gyrojet Census by Serial Number
 
This is a listing of all known (by me) Gyrojet firearms or other firearms owned by MBA during the Gyrojet era. The serial numbers and descriptive notes are based on guns in my collection and in the collections of others, where the data are verified. For other listings, original MBA photographs, online auction sites where Gyrojet serial numbers were included, MBA correspondence, and original MBA inventory sheets, a.k.a., “gun logs” were used.
 
“Butt numbers” on Model 137 pistols refer to the numbers stamped on the bottom of the pistols’ handles after the frames were removed from their die. These served as early serial numbers for Model 137 handguns. When some Model 137 pistols were converted to Mark I guns, the butt numbers were sometimes removed, but not always.
 
Determining total production of a particular model is difficult because some of the firearms were “spoiled” during manufacture and scrapped. The fact that the highest known Model 137 butt number is 144 does not necessarily mean that a minimum of 144 Model 137 pistols were finished and released for sale. MBA gun logs show a Mark II Model C 12mm pistol serial number 606, and the log shows several spoiled guns. An estimate that there were about 600 Mark II Model C pistols produced and released for sale is probably very accurate.
 
This listing represents about 25% of MBA production, so it’s significant but certainly not complete. Your help in adding to the list will be most welcome.
 
Please click HERE to view the census.
 
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