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

Trump Atf Reforms F
Trump Atf Reforms F

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.

PenFed Credit Union Reports Strong Q1 Growth in 2026

Continuing its record of positive growth over the last several years, NRA partner PenFed Credit Union reported increases in capital and liquidity, earning growth and credit quality through the first quarter of 2026.

I Have This Old Gun: Model 1884 Trapdoor Springfield

The U.S. military's first official breechloading service rifle was the Trapdoor Springfield, and of the line of guns that saw use throughout the late 19th century, one of the most refined was the Model 1884 Trapdoor.

A Retro Python: The Pietta Blacktooth Revolver

As the company did with the original Colt Single Action Army, Pietta sought to reproduce the Colt Python as closely to the original as possible with its new Blacktooth revolver.

Interests



Get the best of American Rifleman delivered to your inbox.