Rifleman Q&A: Shotgun Proofmarks?

by
posted on October 24, 2021
** 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. **
Qamain

Q. How do I tell if an old or new shotgun has been “proofed”? My Italian guns seem to be covered with proofmarks—as do a couple old Belgian guns I have—but my American guns don’t seem to have any. How are guns proofed and how do you tell?


A. Proofmarks could be a story or a book themselves. In a nutshell, much can be determined about the origins and to a wide extent the date of manufacture of some shotguns just by examining the proofmarks. A good sampling of proofmarks can be found in the NRA Firearms Fact Book and elsewhere.

Older double guns will primarily carry Belgian or British proofmarks. Many inexpensive shotguns were imported from Belgium for resale in this country, and bear those proofmarks. Many British-made shotguns carry Birmingham proofmarks, with London proofing mainly found on top-of-the-line British shotguns. Over the years, British proofmarks, both Birmingham and London, have changed as the Rules of Proof changed, and often the change in marks can be used to determine during what era a particular shotgun was made.

Unlike Britain and Europe where proofing of firearms is law, in the United States proofing is left to individual manufacturers. To be sure, American-made shotguns are plenty strong, almost to a fault, and following proofing are stamped with the individual manufacturer’s proofmark. The letter “P” superimposed on the bottom of a “W” surrounded by an oval is the familiar Winchester proofmark, Remington uses “REP” within a box, etc.

Proofing involves the firing of an overload that exceeds the service pressure of any given gauge and shell length by about one-third. The cartridges used, clearly marked Proof Loads and informally called “Blue Pills” in this country, are carefully controlled, and available only to firearm manufacturers.

—John M. Taylor


This “Questions & Answers” was featured in the November 2004 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 Q. Cutshaw, Charles M. Fagg, Angus Laidlaw, Evan P. Marshall, Charles E. Petty, Robert B. Pomeranz, O.D., Jon R. Sundra, Jim Supica, A.W.F. Taylerson, John M. Taylor and John Treakle.

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

Latest

Gotw Powder River Precision Rubicon Icon 1
Gotw Powder River Precision Rubicon Icon 1

Gun of the Week: Powder River Precision Rubicon Icon

Powder River Precision has taken the basic Ruger 10/22 rifle concept and enhanced it with its Rubicon Icon design.

The Armed Citizen® May 1, 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.

Training & Gear for Active Shooter Response

For armed civilians, developing an active-shooter response plan isn’t about playing hero. It’s about having the right gear and the skills to decisively use them if violence finds you.

How the Trump Administration is Reforming the ATF

After more than a year of review, the DOJ, and its sub-agency, the ATF, released 34 notices of final and proposed rules to eliminate infringements on Americans’ Second Amendment rights.

A Tale of Two Grips: Building Beyond the First Shot

Every shooter has two grips living inside them, and most never realize it until they are exposed by a timer.

Roni Corporation Establishes U.S.-Based Manufacturing

Roni Corporation—designer and manufacturer of the Micro Roni, PDW-style pistol-to-carbine conversion kits and other firearm accessories—has established U.S.-based operations and manufacturing in Houston, Texas.

Interests



Get the best of American Rifleman delivered to your inbox.