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Spain (1985)

Detailing the development and operational history of the SB 40 LAG 40mm Automatic Grenade Launcher.

 Entry last updated on 9/20/2013; Authored by Staff Writer; Content ©

Basic Specifications
National Flag Graphic
Year: 1985
Type: 40mm Automatic Grenade Launcher
Manufacturer(s): Empresa Nacional Santa Barbara - Spain

The SB-40 LAG is the Spanish contribution to the growing automatic grenade launcher market.

In 1984, design work on an indigenous 40mm automatic grenade launcher was begun in Spain by Empresa Nacional Santa Barbara as a private venture. Adoption by Spanish forces followed in 1992 (as the SB 40 LAG, also written as "SB LAG-40") through an initial preproduction batch of sixty units. The weapon is a contemporary to the American Mk 19 and the Soviet/Russian AGS-17 which have permeated global inventories concerning portable grenade projecting devices.

The SB 40 relies on the long recoil principle which reduces stresses exhibited upon the frame. It makes use of a roller locked system and is chambered for the global standard 40x53mmSR projectile firing from a 24- or 32-round belt. The belt is sat within a hard ammunition case that can be mounted to either the left or right side of the receiver as required (changing requires some internal modification of the system by the user). The weapon achieves a rate-of-fire of 215 rounds-per-minute at a muzzle velocity of 787 feet per second. Available iron sights allow for sighting between 100 and 1,500 meters while grenade effectiveness reaches up to 2,000 meters. Attack angles can vary from line-of-sight to indirect fire as needed, making the SB 40 a flexible tactical weapon. The system is typically fielded on a heavy duty, adjustable tripod though it can also be mounting onto vehicle, watercraft and helicopter pintle mounts.

Outwardly, the SB 40 takes on the appearance of the American Mk 19 with its decidedly rectangular receiver, spade-type grips at the rear and short barrel assembly at the front. Sights are affixed across the top of the receiver in the usual way and a cocking handle controls the feed/bolt during the initial charge. Dimensionally, the SB 40 is a large weapon despite it being portable and it weighs upwards of 75lbs, features an overall length of 38 inches and sports barrel of 16.3 inches long.

The modern Spanish military utilizes the SB 40 as a support weapon at the infantry level and has mounted it atop their various four- and six-wheeled armored vehicles as well as tracked armored personnel carriers. The major issue variant is recognized as the "40 SB-M1". Columbia remains the only other notable operator of the SB 40 system (as of 2013) for it has accepted a stock of SB 40 grenade launchers for mounting onto their navy patrol boats.
Supported Mission Types
Frontline Infantry
Special Forces
Close Quarters Battle
Designated Marksman/Sharpshooter
Area Effect/Suppression
Indirect Fire
Airspace Denial
Attachment Weapon
Internal Design, Weight and Dimensions
Firing Action: Roller-Locked, Recoil-Operated; Automatic Fire
Available Caliber(s): 40x53mmSR
Ammunition Count / Feed: 24- or 32-round belt
Weight (Empty): 74.96 lb (34.00 kg)
Overall Length: 960 mm (37.80 in)
Barrel Length: 415 mm (16.34 in)
Sighting Assist: Iron Leaf Rear

Operating Performance
Muzzle Velocity: 790 ft/sec (241 m/sec)
Rate-of-Fire (RoF): 215 rounds-per-minute (rpm)
Typical Range: 2,600 feet (792 m; 867 yd)

Operators List
Colombia; Spain

Model Variants
• SB 40 LAG - Base series designation
• SB LAG-40 - Alternative Designation
• 40 SB-M1 - Spanish Army Designation