5.7x28 mm FN Cartridge Standardized By SAAMI

by
posted on October 3, 2024
** 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. **
5.7x28 mm FN cartridge drawing SPORTING ARMS & AMMUNITION MANUFACTURERS' INSTITUTE lines numbers bullet
Photo courtesy of SAAMI.org.

The 5.7x28 mm FN centerfire pistol and revolver cartridge has been accepted by the Sporting Arms and Ammunition Manufacturers’ Institute (SAAMI). Its standard specifications were published in late August. FN Herstal, S.A., designed it, and the proposal for standardization came from SAAMI voting member Fiocchi of America, in partnership with FN America.

It features a 40-grain bullet traveling at a velocity of 1,750 f.p.s. from a 5" test barrel at a maximum average pressure of 48,500 p.s.i. Full specifications, including mechanical drawings, are found on SAAMI’s technical drawing page.

Design of the 5.7x28 mm FN began at FN Herstal, S.A., in the 1980s, when the North Atlantic Treaty Organization (NATO) was in search of pistol ammunition with better performance than the 9 mm NATO. An application for the new cartridge was filed with the U.S. Patent Office in 1989 and the first load was revealed to the public in 1990. The earliest firearms to chamber it were FN’s FN P90 and FiveseveN. Today, guns in the chambering are offered by nearly every major manufacturer. 

NATO standardized the cartridge in 2021, integrating it into its Multi-Caliber Manual Of Proof and Inspection list. It joined 9 mm NATO, 5.56 mm NATO, 7.62 mm NATO and 12.7x99 mm NATO (more widely known as the .50 BMG).

FN Herstal has developed several of the world’s most popular cartridges. The 5.56 NATO and 7.62 NATO—standardized by NATO in 1957 and 1981, respectively—were company designs. Acceptance by SAAMI underscores the firm’s dedication to providing law-abiding citizens, armed forces and security forces with high-performance and efficient small-caliber ammunition.

SAAMI was founded in 1926 at the request of the Federal government. The organization is the leader in promoting firearm safety by creating standards that ensure safety, reliability and interchangeability of ammunition, components and firearms.

Latest

.308 Win.
.308 Win.

Handloads: A Quiet .308 Win. For Large-Format Pistols

Of the many commercial .308 Winchester loads, few, if any, are designed for barrels shorter than 16". The one that follows helps address this gap while remaining simple to suppress and light on the wrists.

Court Approves Watchtower Firearms DIP Financing

Watchtower Firearms was granted final approval for debtor-in-possession (DIP) financing by the U.S. Bankruptcy Court for the Northern District of Texas in late June.

Review: Ruger LC Carbine In 10 mm Auto

Following the success of its .45 ACP-chambered LC Carbine, Ruger realized that this platform would go a long way toward making the 10 mm Auto more controllable and fun to shoot, and a new 10 mm version was released in 2024.

The Armed Citizen® July 14, 2025

Read today's "The Armed Citizen" entry for real stories of law-abiding citizens, past and present, who used their firearms to save lives.

Favorite Firearms: A Little Stevens From Chicago

"Over the next five or six years, and before I went off to college, I fired hundreds and hundreds of rounds of .22 BB Caps, CB Caps, Shorts and Longs through this rifle."

Preview: Strike Industries T-Bone Charging Handle

The T-Bone from Strike Industries is an ideal fit for suppressed applications, as it can be configured by the user to redirect gas blowback entirely to either side ...

Interests



Get the best of American Rifleman delivered to your inbox.