txinvestigator wrote:Thanks!Arock wrote:txinvestigator wrote:Isn't the P7 gas operated too? They are cool little guns.
Gas-delayed blowback (also called gas-retarded blowback) is a firearm operating principle (not to be confused with gas-operated). The bolt is never really locked, and so is pushed rearward by the expanding propellant gases as in other blowback-based designs. However, propellant gases are vented from the barrel into a cylinder with a piston that delays the opening of the bolt.
Gas-delayed blowback is one of the rarer operating principles. It is used by the HK P7 and Steyr GB pistols.
Arock
txi, I should have explained in more detail than just posting a pic. The .45ACP cartridge is a low-pressure round. Lower pressure than contemporary 9mm cartridges. Too low, in fact, for reliable gas actuation of the piston. To compensate for this HK designed a hydraulic piston system but that proved too expensive to build and sell.
Also need to correct an earlier statement. There are SIX prototype P7M7 pistols. All built in 1983. They are still resident at the HK factory. One has a 1985 date stamp but it is still believed to have been part of the 1983 prototype production. There are allegations one pistol surfaced for sale in Hawaii for $10,000 a few years ago but this is widely dismissed. Any P7M7 that changed hands today would fetch a good bit more than that.
Arock
