SAAMI Accepts .300 HAM'R Cartridge

by
posted on February 11, 2020
** 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. **
300-hamr-gains-saami-acceptance-f.jpg
The Sporting Arms and Ammunition Manufacturers’ Institute (SAAMI)—the organization that creates industry standards to ensure the safety, reliability and interchangeability of firearms, ammunition and components—has officially accepted the .300 HAM’R rifle cartridge and published [PDF] its specifications. The cartridge, developed by SIG Sauer, was introduced with a maximum average pressure (MAP) of 57,500 psi with a 125-grain bullet at a velocity 2,450 fps or 130-grain load at 2,425 fps.

Wilson Combat first introduced the cartridge to enthusiasts in 2018, releasing a variety complete ARs and barrels along with ammunition. The company issued a press release last week, thanking, “…Starline Brass of Sedalia, MO, Western Powers of Miles City, MT, and SIG Sauer Ammunition of Jacksonville, AR, for their assistance during development and extra thanks to SIG Sauer Ammunition for submitting the cartridge to SAAMI.”

The .30-caliber cartridge is designed to optimize the performance of 95- to 150-grain bullets and function in the AR-15 platform. Muzzle velocities range from 2,280 fps to 2,770 fps out of a 16-inch barrel, depending bullet weight, while still adhering to the maximum average pressure specification of 57,500 psi.
SAAMI specification drawing showing the dimensions of the 300 HAM'R cartridge.

It is tailored for self-defense, law enforcement and hunting applications and features terminal performance comparable to the .30-30 Win. It has, however, a flatter trajectory than the legendary cartridge, due to the bullet’s higher ballistic coefficient.

Changing an existing AR-15 to digest .300 HAM’R requires only a barrel change and the use of 300 BLK magazines. Starline Brass produces casings for enthusiasts who prefer to reload, although more common .223 Rem. and 5.56 mm NATO casings can also be resized.

A line of factory ammunition is available from Wilson Combat for a variety of purposes. It recently added two new loads to the lineup; one with a 110-grain solid copper Barnes Tipped Triple-Shock X bullet, with the other featuring a Wilson Combat/Speer 150-grain HAM’R bonded bullet.

Latest

National Firearm Act
National Firearm Act

150,000 NFA Applications Filed On Day 1 After $0 Tax Stamp Becomes Official

Approximately 150,000 NFA enthusiasts filed their paperwork through ATF’s electronic system in just the first 24 hours of 2026, the first day after the $0 tax stamp for most NFA items became official.

Gun Of The Week: Caracal USA CMP9K

Caracal's CMP9K pistol is based on a design originally produced to replace the aging stock of Heckler & Koch MP5s in United Arab Emirates service.

The Armed Citizen® Jan. 9, 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.

Preview: Roundhouse Provisions Ultimate Campout Kit

Founded by Chuck Norris (yes, that Chuck Norris), Roundhouse Provisions is a company that produces emergency foodstuffs designed to be quickly and simply prepared that will stay fresh for years.

New For 2026: Taurus TX9 Pistol

Taurus launches the TX9 family of striker-fired, polymer-frame pistols, adding to its popular TX series of handguns.

Heavy Browning At War: Combat Tales Of The Browning M1917 Machine Gun

For the first half of the 20th century, one of the most important firearms in the U.S. military arsenal was the water-cooled Browning M1917, known to gunners and infantrymen alike as the "Heavy Browning."

Interests



Get the best of American Rifleman delivered to your inbox.