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Preview – Project 32 PTR-32K PDW

Photos by Mark Kuczka and Carmen Lout

The Best Kept Secret of When East Met West

In November 1989, the fortified wall separating East and West Germany would officially come down and no longer divide a city, families, cultures, or even ideology. The Cold War was officially over, and a new reunified Germany was born. Similarly, Project 32 was also born, but it would take 26 long years to complete. Born of a little-known Heckler & Koch variant, the concept would never see the light of day for decades, until a little company from South Carolina with a well-developed reputation for producing HK clones made the decision to resurrect the secretive HK-32.

The history of Project 32 began in 1943. During World War II, the Soviets initiated development of a new intermediate military cartridge, the 7.62×39, after encountering the German 7.92×33 Kurz. This development continued through the end of the war, and by 1947 the cartridge was in full production for use in the newly introduced Avtomat Kalashnikova, model of 1947, now known around the World as the AK-47. The 7.62×39 typically launches a 123-grain projectile at around 2,350 feet per second. Offering significantly more power than the 7.62×25 Tokarev pistol cartridge used in submachine guns, combined with significantly less recoil than the full powered 7.62x54R rifle cartridge, the 7.62×39 was the perfect blend of power, range, and performance. Seventy years later the cartridge is still encountered around the globe as one of the most prolific ever produced.

After the defeat of Nazi Germany in 1945, Germany was divided up amongst the Allies. This division eventually broke down into ideological lines with America and her allies controlling what became known as West Germany and communist Russia controlling East Germany. In 1959, the West German Army selected the Spanish CETME (Center for Technical Studies of Special Materials) rifle in 7.62×51 for adoption and negotiated a license for Rheinmetall and HK to domestically manufacture the rifle in Germany as the G3. Eventually, HK marketed a civilian version of the G3 known as the HK-91.

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In typical German fashion, the G3/HK-91 was a marvel of over-engineering. While the world’s firearms designers were offering designs using long-stroke or short-stroke pistons, direct impingement systems, rotating bolts, locking blocks, or combinations of designs, the German engineers chose a new path by designing a roller-locked, delayed blowback system. German engineer Ludwig Vorgrimler, while working at the Spanish government facility CETME, and based upon his previous work with the Sturmgewehr 45, developed the now famous CETME rifle. In very simplistic language, Vorgrimler looked at a straight blowback operating system designed for use in submachine guns chambered for the little 9mm pistol cartridge and thought, How can we make this work with a 7.62×51 full power battle rifle cartridge?

After a few years of development, that evil little genius kicked out the now famous CETME/G3 rifle. While one can debate the merits of the roller-locked, delayed blowback operating system, you have to marvel at its operation. When the bolt closes, it locks into the barrel extension by means of two small cylindrical rollers being forced outwards into matching recesses in the barrel extension by a locking wedge located inside the bolt head. Upon firing, the recoil energy pushes back against the bolt head and compresses the rollers inward, retracting them from their barrel extension recesses.

By the time the rollers have fully retracted from their recesses, chamber pressures have dropped to a safe level, allowing the locking piece to move slightly to the rear where it engages with the bolt carrier. Both the locking piece and the bolt carrier move rearward as a single unit, allowing the rifle to begin the cycling process. While this is a very simple explanation of a very complicated process, the operating system essentially works using the recoil energy of the cartridge.

Think about that for a second. The system is not dependent upon captured gas, gas blocks, powder burn rates, or barrel gas port diameters — none of it. It’s totally dependent upon the recoil energy from the fired cartridge. There’s nothing to foul, break, come loose, or erode out of specification. In theory, it’s a very clean system that works with an extremely wide range of bullet weights and powder combinations. In reality, G3/HK-91 rifles with the roller-locked delayed blowback operating system have a 50-plus-year history of outstanding service as one the most reliable and durable 7.62×51 rifles ever produced, even if they do launch cases into low earth orbit.

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