Smith & Wesson QSPR
Quiet Special Purpose Revolver
Some S&W model 29s were rebuilt by the AAI Corporation to make the Quiet Special Purpose Revolvers (QSPR).
These had new, short, smoothbore barrels (35 mm / 1.375 inch), with .40" / 10mm bore, and with cylinder chambers reamed to accept special QSPR ammunition which externally resembled metal-cased .410-gauge shotgun shells but internally worked as a piston to trap the gases.
This special ammunition was also made by AAI.
This pistol was developed from 1967-1971 to be used by tunnel rats in the Vietnam War. The QSPR was tested on the battlefield in 1969, an improvement and testing program ran 1970 till 1971.
At least officially it never entered service.
The US withdrawal from Vietnam reduced interest in the QSPR weapon, and the program was ended about 1972.
Marcel
