5.56x45 mm cartridge

The 5.56x45 mm cartridge is the NATO-standard intermediate rifle round associated here with the Bulgarian AR-M9 and AR-M9F rifles. FN Herstal identifies the 5.56x45 mm SS109 cartridge as the original NATO-standardized military 5.56 round, adopted in 1980, and lists it for carbines, assault rifles, and light support weapons.

5.56x45 mm cartridge, 5.56x45 mm NATO rifle cartridge, Munitions

Image source: Cartridge 5.56x45mm NATO CC BY-SA 4.0 by Grasyl.jpg

Profile

Origin: Belgium / NATO
Built by: FN Herstal
Built in: Belgium
Type: 5.56x45 mm NATO rifle cartridge
Service note: Late Cold War to present NATO standard rifle ammunition

cartridge NATO portable

Specifications

Caliber: 5.56x45 mm NATO
Standard cartridge: SS109
Ammunition types: SS109 ball, L110 tracer, and blank
Uses: Carbines, assault rifles, and light support weapons
Standardization: Adopted by NATO as the second official standardized calibre in 1980

Service And Conflict Use

Service History

In service: Standard NATO rifle cartridge family since 1980
Used by: Carbines, Assault rifles, Light support weapons

Compatible Firearms

This page links the cartridge family to the rifle family explicitly identified by the manufacturer as 5.56x45 mm.

Compatible item

Item type

Compatibility evidence

Arsenal AR-M9 / AR-M9F

5.56x45 mm assault rifle

Arsenal's AR-M9 and AR-M9F product pages identify both rifles in the 5.56x45 mm family, so they belong on the cartridge's compatibility page.

Sources: Bulgarian AR-M9 & AR-M9F rifles supplied by UAE to allied forces, 5.56x45 mm and 7.62x39 mm AR-M9, 5.56x45 mm and 7.62x39 mm AR-M9F

5.56x45 mm cartridge Videos

A Brief History of 5.56x45mm NATO

5.56x45 mm cartridge Images

5.56x45 mm cartridge, 5.56x45 mm NATO rifle cartridge, Munitions - view 1 — Source: Cartridge 5.56x45mm NATO CC BY-SA 4.0 by Grasyl.jpg

5.56x45 mm cartridge, 5.56x45 mm NATO rifle cartridge, Munitions - view 2 — Source: Caliber cartridge comparison - .223 Remington and 5.56x45mm NATO.jpg

Related Weapon Systems

.308 Winchester cartridge, Centerfire rifle cartridge in .308 Win, Munitions

Munitions.308 Winchester cartridgeCenterfire rifle cartridge in .308 Win.308 Winchester is a centerfire rifle cartridge introduced by Winchester and now widely offered by major ammunition manufacturers for hunting, match, and general sporting use. This relationship-only catalog page records the cartridge as the ammunition family fired by .308 Win-chambered rifles, without inheriting any conflict-use claims from a parent weapon page.

5.56x45mm NATO cartridge, 5.56x45mm NATO small-arms cartridge, Munitions

Munitions5.56x45mm NATO cartridge5.56x45mm NATO small-arms cartridgeThe 5.56x45mm NATO cartridge is a NATO-standard small-arms cartridge in FN Herstal's SS109 lineage, and Colt identifies the AR15A4 Rifle as chambered in 5.56x45mm. This relationship-only page captures the cartridge's technical context and direct rifle match without inheriting conflict-use claims from the rifle page.

7.62x51mm NATO cartridge, NATO standard rifle cartridge, Munitions

Munitions7.62x51mm NATO cartridgeNATO standard rifle cartridgeThe 7.62x51mm NATO cartridge is a rimless, bottlenecked NATO-standard rifle round loaded by military and commercial manufacturers for rifles, designated marksman rifles, and machine guns. This relationship-only page keeps the cartridge separate from weapon-specific conflict history while linking it to cataloged rifles that are documented as chambered for it.

12.7x99mm NATO / .50 BMG, 12.7 mm heavy machine-gun cartridge, Munitions

Munitions12.7x99mm NATO / .50 BMG12.7 mm heavy machine-gun cartridge12.7x99mm NATO, also known as .50 BMG, is the heavy-machine-gun cartridge family associated with M2-class weapons and other .50-caliber systems. This relationship-only page documents the cartridge, linked-belt feed context, and common load families without adding unsourced conflict-use claims.

5.45×39mm cartridge, Soviet intermediate rifle cartridge, Munitions

Munitions5.45×39mm cartridgeSoviet intermediate rifle cartridgeThe 5.45×39mm cartridge is a Soviet intermediate rifle round developed for the AK-74 family and still in service. This relationship-only page records the cartridge's origin, basic specifications, and the cataloged rifles that fire it without inheriting conflict-use claims from the parent weapon page.

7.62x39mm cartridge, Intermediate rifle cartridge, Munitions

Munitions7.62x39mm cartridgeIntermediate rifle cartridgeThe 7.62x39mm cartridge is a Soviet intermediate rifle round adopted in the 1940s and still widely used in Kalashnikov-pattern rifles. This page documents the cartridge's technical identity and its direct compatibility with the AK-103-2 assault rifle.

Sources

FN Herstal 5.56x45mm NATOPublisher: FN Herstal | Note: Supports manufacturer background, the 5.56x45 mm SS109 designation, NATO standardization in 1980, and the listed uses for carbines, assault rifles, and light support weapons. | Accessed: 2026-06-23 Bulgarian AR-M9 & AR-M9F rifles supplied by UAE to allied forcesPublisher: Armament Research Services | Note: Supports the AR-M9 / AR-M9F caliber identification and the linked rifle-family context used for the reciprocal relationship section. | Accessed: 2026-06-23 5.56x45 mm and 7.62x39 mm AR-M9Publisher: Arsenal JSCo | Note: Supports manufacturer background for the AR-M9 rifle family and its 5.56x45 mm / 7.62x39 mm product category. | Accessed: 2026-06-23 5.56x45 mm and 7.62x39 mm AR-M9FPublisher: Arsenal JSCo | Note: Supports manufacturer background for the folding-stock AR-M9F variant and its 5.56x45 mm / 7.62x39 mm product category. | Accessed: 2026-06-23 Cartridge 5.56x45mm NATO CC BY-SA 4.0 by Grasyl.jpgPublisher: Wikimedia Commons | Note: Image provenance for the primary 5.56x45 mm cartridge photograph. | Accessed: 2026-06-23 Caliber cartridge comparison - .223 Remington and 5.56x45mm NATO.jpgPublisher: Wikimedia Commons | Note: Image provenance for a cartridge comparison image that includes 5.56x45 mm NATO. | Accessed: 2026-06-23