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

Armed Citizen Podcast John Lott 1
Armed Citizen Podcast John Lott 1

Why the Murder Rate Quickly Fell to a Likely Historic Low

If the gun-control Left is to be believed, then the murder rate in the U.S. should be going up. After all, gun sales and ownership rates have been rising for the last few decades and anti-gun groups claim that gun ownership is the cause of violent crime. This, of course, is nonsense.

16 New Bolt-Action Rifles for 2026

From cutting-edge precision rifles designed for competition or hunting to traditionally styled guns that emulate designs from yesteryear, 2026 saw the introduction of an incredible array of bolt-action rifles.

Review: Chiappa Rhino 60DS 10 mm Auto

The Italian-designed-and-manufactured Chiappa Rhino remains unique today as the only current revolver with the barrel mounted at the bottom of the frame, firing from the chamber at the 6-o’clock position.

5 New Large-Format Pistols for 2026

There's been a huge surge in the large-format pistol category, and 2026 continues to showcase new models answering the wants and needs of today's firearm owners.

Short & Powerful: The EOTech Vudu 4-12x36 mm Super Short Riflescope

EOTech's ultra-compact 3-9x32 mm Vudu was a popular addition to the company's variable-powered riflescope line, and the new 4-12x36 mm Vudu ups the ante with new features in a still-compact package.

The Armed Citizen® May 11, 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.

Interests



Get the best of American Rifleman delivered to your inbox.