Automatkarbin 5
The Automatkarbin 5 (Ak 5), meaning "automatic carbine 5" in Swedish, is a selective-fire assault rifle chambered in 5.56×45mm NATO that serves as the standard-issue service rifle for the Swedish Armed Forces, developed as a licensed and modified variant of the Belgian FN FNC design to suit subarctic operational environments.[1] Adopted in 1986, it replaced the earlier Ak 4 (a licensed Heckler & Koch G3) and has been produced domestically by FFV Ordnance AB (later Saab Bofors Dynamics), with initial units sourced from Fabrique Nationale in Belgium.[2] The rifle features a gas-operated, rotating bolt action with a 17.7-inch (450 mm) barrel, weighs 8.5 pounds (3.9 kg) empty, and achieves a cyclic rate of fire of 675 rounds per minute, with an effective range of approximately 400 meters.[1] Key modifications to the base FN FNC include adaptations for cold-weather reliability, such as enhanced lubrication systems and corrosion-resistant finishes, ensuring functionality in Sweden's harsh climate.[2] It feeds from 30-round detachable box magazines and offers selective fire modes including safe, semi-automatic, and full-automatic, with iron sights adjustable out to 400 meters and provisions for optics.[1][3] Over 190,000 units of the original Ak 5 have been produced, making it a cornerstone of Swedish infantry armament since its introduction.[4] The rifle has seen deployment in international peacekeeping operations, including missions in Kosovo, Afghanistan, Chad, Lebanon, and Macedonia.[1] Several variants have extended the Ak 5's service life and versatility. The Ak 5B, introduced for designated marksman roles, incorporates the British L9A1 SUSAT 4×25.5 optic and was produced in limited numbers (approximately 5,200 units).[1] The Ak 5C, modernized in 2006, features a modular design with Picatinny rails for accessories like the Aimpoint CompM2 red dot sight, an adjustable stock, and improved ergonomics for compatibility with modern combat optics and grips.[5] Shorter carbine versions include the Ak 5D for vehicle crews and close-quarters battle, with a reduced barrel length, and the updated Ak 5D Mk II combining D-model compactness with C-model enhancements.[1] As of 2023, the Swedish Armed Forces initiated procurement of the Ak 24 (initially designated self-defense weapon) from Sako as a successor, with deliveries beginning in 2024—including the first 1,200 units received in November 2024 and additional orders for up to 22,500 more through 2025—signaling the Ak 5's impending phase-out while it remains in active use alongside NATO allies.[6][7]Development and history
Background and development
In the post-World War II era, Sweden's small arms development emphasized self-sufficiency and adaptation to harsh northern environments, evolving from bolt-action Mauser rifles and semi-automatic Ljungman Ag m/42 designs to more modern systems aligned with NATO standards. By the 1960s, the Swedish Armed Forces adopted the Ak 4, a licensed variant of the Heckler & Koch G3 chambered in 7.62×51mm NATO, but by the 1970s, NATO's shift toward the lighter 5.56×45mm NATO cartridge created pressure for standardization, highlighting the need to replace the heavier Ak 4 to improve soldier mobility and logistics compatibility.[8][2] To identify a suitable successor, the Swedish military initiated comprehensive trials in 1975–1976, focusing on cold-weather reliability and evaluating both domestic prototypes and international designs, including the Colt AR-15, Steyr AUG bullpup, and the indigenous GRAM experimental rifle developed by Carl Gustafs Stads Gevärsfaktori. Further evaluations from 1979–1980 at the I 11 Infantry Regiment in Växjö tested narrowed contenders, such as the FFV 890C (a modified Israeli Galil) and the Belgian FN FNC, with the FN FNC demonstrating superior performance in subzero conditions despite the FFV 890C's technical edge in some areas. The FN FNC was ultimately selected in 1982 due to its cost-effective stamped-metal construction, ease of local production using existing tooling from Ak 4 manufacturing, and political considerations favoring Belgian neutrality over Israeli ties.[9][2] Following selection, FFV Ordnance (later part of Bofors) began modifications in 1982 to optimize the FN FNC for Sweden's subarctic climate, incorporating enhancements like dual gas port settings for reliable operation in extreme cold and contamination, improved magazine followers to prevent freezing, and a redesigned stock for better handling with heavy winter clothing. These changes were rigorously tested in Swedish environments from 1982–1985, including arctic field trials simulating prolonged exposure to snow, ice, and low temperatures, ensuring the rifle's functionality across seasonal extremes. The refined design was formally adopted as the Automatkarbin 5 in 1986, marking the culmination of over a decade of development to meet Sweden's unique operational demands.[8][9]Production and adoption
Production of the Automatkarbin 5 began in 1985–1986, initially with units supplied directly from FN Herstal in Belgium before licensed manufacturing commenced in Sweden by FFV Ordnance AB.[2] In the 1990s, responsibility for production transitioned to Saab Bofors Dynamics (now Saab Dynamics), which has overseen subsequent manufacturing at facilities in Eskilstuna and Karlsborg along with ongoing maintenance and upgrades.[1][10] Approximately 190,000 units of the original Ak 5 and around 5,200 of the Ak 5B variant had been produced, with additional units of later variants bringing the total to over 200,000 across all variants.[4][11] The rifle received its official designation as Automatkarbin 5 in 1986 and was adopted as the standard service rifle of the Swedish Armed Forces, marking a partial replacement for the earlier Ak 4 that was fully completed by the early 1990s.[2] In 2023, Sweden and Finland announced a joint program to develop the Automatkarbin 24 in collaboration with Sako Ltd., intended as the eventual successor to the Ak 5 by the late 2020s. As of 2025, initial deliveries of the Ak 24 have commenced to the Swedish Armed Forces, with approximately 37,500 units planned for delivery by the end of 2026 under current contracts. However, deliveries faced delays, leading to the interim acquisition of 15,000 Colt M4A1 rifles in December 2024. In March 2025, a temporary ban was imposed on Ak 24 use due to technical issues with the firing mechanism, remaining in effect pending full inspections and resolution.[12][13][14][15]Design
Operating system and features
The Automatkarbin 5 utilizes a gas-operated, long-stroke piston system with a rotating bolt locking mechanism, derived from the design principles of the Belgian FN FNC rifle.[16][17] This configuration ensures reliable cycling by directing propellant gases to drive the piston rearward, which is rigidly attached to the bolt carrier, unlocking and extracting the spent cartridge before chambering a new round. The system's cyclic rate of fire ranges from 650 to 700 rounds per minute, providing controlled automatic fire while maintaining operational stability.[18] An adjustable gas regulator at the front of the gas block allows fine-tuning of gas flow to optimize performance across varying ammunition types and environmental conditions, enhancing reliability in adverse scenarios such as fouling or suppressors.[19] Key ergonomic features include a folding metal stock that adjusts for user comfort and transport, ambidextrous selector levers for intuitive operation by left- or right-handed shooters, and an enlarged trigger guard designed to accommodate gloved hands during cold-weather operations.[20][3] The rifle also features compatibility with standard STANAG magazines, modified from the original FN FNC design to ensure interchangeability with NATO-standard 30-round box magazines.[16] These elements prioritize ease of use in the field, particularly for Swedish forces operating in subarctic environments. Adaptations for subarctic conditions encompass a corrosion-resistant phosphate finish applied to metal components, which protects against moisture and salt exposure common in harsh winters, and a redesigned handguard that facilitates secure handling in low temperatures without freezing to the skin.[16][21] The mechanism incorporates tolerances to prevent ice buildup and maintains functionality with specialized low-temperature lubricants, ensuring consistent operation down to -30°C.[3] Additionally, the cocking handle and bolt assembly are oversized for gloved manipulation, reducing the risk of operational delays in extreme cold.[20] The firing system supports selective fire modes, including safe, semi-automatic, and full-automatic, with the selector mechanism integrated into the receiver for quick mode changes.[16] The baseline model and variants emphasize semi- and full-automatic for versatility in combat. The rotating bolt provides secure lockup during firing, contributing to the rifle's overall durability and safety under sustained use.[18]Specifications
The Automatkarbin 5 (Ak 5) is a selective-fire assault rifle chambered in 5.56×45mm NATO, utilizing a gas-operated rotating bolt action.[16][3]| Specification | Details |
|---|---|
| Caliber | 5.56×45mm NATO[16][3] |
| Barrel length | 450 mm (standard)[16][3] |
| Overall length | 1,008 mm (stock extended); 753 mm (stock folded)[16] |
| Weight (unloaded) | 3.9 kg[16][3] |
| Muzzle velocity | 925 m/s (with SS109 cartridge)[22] |
| Effective range | 400 m[22][3] |
| Rate of fire (cyclic) | 650–700 rounds per minute[16][3] |
| Feed system | 30-round detachable STANAG-compatible box magazine[16][3] |
| Sights | Adjustable iron sights with two-position flip rear aperture (250 m and 400 m); hooded front post sight[3] |