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

by
posted on October 14, 2022
** When you buy products through the links on our site, we may earn a commission that supports NRA's mission to protect, preserve and defend the Second Amendment. **
HRHK4

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.

To subscribe to the magazine, visit the NRA membership page and select American Rifleman as your member magazine.

Latest

Springfield Armory Model 2020 Boundary Gotw 1
Springfield Armory Model 2020 Boundary Gotw 1

Gun of the Week: Springfield Armory Model 2020 Boundary

While the company's initial Model 2020 Waypoint design was intended to be more of a precision platform, Springfield has since come out with several field-ready variants of the Model 2020, including the Boundary.

Standing Guard | The NRA and Freedom’s 250th

A quarter of a millennium ago this July 4, John Hancock was the first to sign the Declaration of Independence.

The Armed Citizen® June 19, 2026

Read today's "The Armed Citizen" entry for real stories of law-abiding citizens, past and present, who used their firearms to save lives.

The Supreme Court Goes 9-0 on United States v. Hemani

In United States v. Hemani, The Supreme Court decided that the federal statute that prohibits the possession or ownership of firearms by a person who “is an unlawful user of or addicted to any controlled substance” violates the Second Amendment when applied to regular marijuana users.

FN Improves Iconic MAG Machine Gun

The FN MAG, better known to Americans as the M240 machine gun, has been in U.S. military service since 1976, and this year, the platform has gotten some serious upgrades.

Switching It Up In West Texas: The WTO SwitchLug System

The SwitchLug by WTO is designed for popular rifles, and it’s a modern system that doesn’t require buying new rifle.

Interests



Get the best of American Rifleman delivered to your inbox.