7 mm Merrill

by
posted on November 10, 2014
** 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. **
ram.jpg

I am pleased to say that the original idea for this wildcat cartridge was mine. Since I am the most un-mechanical male on the planet, the actual development of the cartridge had to be done by Bob Smith and (mostly) Jim Rock of RPM (Rock Pistol Manufacturing). These guys know about mills and lathes and all. We all wanted a moderate velocity handgun cartridge in 7 mm, as that bore size looked to be just the ticket for long-range handgun work. It was the 70s and the heyday of IHMSA (International Handgun Metallic Silhouette Association) matches. Targets were the thick steel cutouts of animals, placed at as much as 200 meters from the firing line. Since the targets were heavy, it took a pretty powerful blow to topple one. That’s particularly true of the 200 meter ram, which weighed 54 pounds. The range mandated an accurate cartridge with a flat trajectory.

It was a blue-collar sport and the founders were sensitive to the economics of shooting, so inexpensive single shot pistols were the order of the day—Contenders and Merrills. In these guns, a rimmed cartridge was clearly superior to all others, so I spent a lot of time pouring over ammunition manuals and loading books. I wanted a rimmed case (for easy extraction) with a medium powder capacity and convertible to 7 mm. There were no super computer programs to do the searching for you in those times.

After no small amount of effort, the lightbulb over my head went blink one night. My base cartridge was the .225 Win. It was based on the venerable .30-30 and designed by Winchester to replace the .220 Swift. Unlike a couple of other 7 mm wildcats, we gave the 7 mm Merrill the same shoulder angle as the 7 mm Rem. Mag. Using medium- to heavy 7 mm bullets in neck-expanded and fire-formed .225 cases, we got power, flat trajectory, accuracy and (barely) bearable recoil. I was happy to be associated with the project.

Latest

Magpul Hunter Lite Stock
Magpul Hunter Lite Stock

New for 2026: New Products from Magpul

Magpul announces new metal-magazines, new stocks and pistol frames.

New for 2026: Burris Veracity Riflescopes

The latest generation of Veracity scopes is available in a variety of 5X magnification ranges.

New for 2026: Springfield Armory 10-8 Performance Master Class 1911 Pistols

Springfield Armory and Lipseys have partnered to offer a highly custom 1911 with input from Hilton Yam.

New For 2026: Diamondback SDR-A

Following the release of its Self-Defense Revolver in 2024, Diamondback Firearms has now lightened its design and reduced the cost with the new-for-2026 SDR-A.

Rifleman Review: Walther Arms PDP F-Series 4-Inch

Walther Arms continues to expand its F-Series handgun line, a design initially developed for women but that has broad appeal across the firearm consumer market, thanks to its unique design elements and feature set.

Mossberg Expands Budget-Priced Maverick Line With Semi-Auto Model

As part of its International family of shotguns, Mossberg announced the introduction of the Maverick SA Semi-Auto, a versatile, value-focused semi-automatic platform built to deliver reliable performance.

Interests



Get the best of American Rifleman delivered to your inbox.