Rifleman Q&A: A Convertible Semi-Automatic H&R Pistol?

posted on October 14, 2022

Q. I recently acquired an unusual, compact, semi-automatic pistol. I don’t know much about it. The slide is marked “Harrington & Richardson, Inc. Worchester, Mass. USA, Made in Germany Mod. HK4 Cal. 380.” There is also a lion stamped between the dates 1871 and 1971. Can you tell me what I have?

A. It appears you have an HK4 .380 ACP pistol made by Heckler & Koch in Germany. This is a blowback-operated semi-automatic pistol based on the Mauser HSc design of the 1930s. They were chambered for .22 LR, .25 ACP, .32 ACP and .380 ACP cartridges. These calibers were easily converted by switching the barrels, recoil springs and magazines. The rimfire model could be changed by rotating the breechface. Conversion kits were available for all calibers. The barrel is 3” long, and the finish is blued. The molded plastic grips feature thumb rests. The pistol was sold from 1968 to 1973 as the Harrington & Richardson HK4 and is so marked. The HK4 was completely discontinued in 1984.

—Harry Hunter

This “Questions & Answers” was featured in the October 2009 issue of American Rifleman. At time of publication, "Questions & Answers" was compiled by Staff, Ballistics Editor William C. Davis, Jr., and Contributing Editors: David Andrews, Hugh C. Birnbaum, Bruce N. Canfield, O. Reid Coffield, Charles M. Fagg, Angus Laidlaw, Harry Hunter, Charles E. Petty, Jon R. Sundra, Jim Supica, John M. Taylor and John W. Treakle.

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