The Noble M500 is a semi-automatic submachine gun produced by the Spanish defense manufacturer Grupo Hispano- a recoil-operated, blowback-operated, selective-fire weapon capable of firing in either single-fire or full-automatic modes. The M500 is a compact, lightweight, and highly concealable weapon with a bullpup layout explicitly made for operators who need tactical flexibility, accuracy, and fire rate, in a lightweight package. The gun also features a modular design, allowing operators to swap certain parts depending on the mission.
The M500 is derived from the earlier M300 and M400 series of submachine guns. Hispano developed the M300 line from the earlier HÉ-5 submachine gun. The HÉ-5 is based on the FN P90 personal defense weapon, which was based on the FN MAG general-purpose machine gun. Like the HÉ-5, the M300 series of submachine guns are also blowback-operated, recoil-operated firearms with a side-mounted magazine and a detachable stock. This stock can be removed for ease of storage or increased portability. The M300 series is also outwardly similar to the FAMAS, also derived from the P90 personal defense weapon. Like the P90, the M300 series is also a bullpup layout submachine gun with a short barrel positioned forward of the trigger group, a pistol grip, and a pistol-type handgrip at the bottom of the pistol grip. The magazine is inserted forwards of the trigger group before it enters a curved channel in the buttstock. The pistol grip contains the trigger group and its return spring.
The M400 series of submachine guns were developed from this M300 series and features a new lower receiver with internal modifications to accommodate different magazines and mounting options. The M500 was developed from this M400 series, with new polymer furniture and other changes to improve ergonomics, weight distribution, ease of maintenance, and overall performance. Production of this weapon began in 1998, with first deliveries starting in 1999.
The weapon features an integrated Picatinny rail for mounting optics or other sights for aiming purposes; a flash suppressor is located on top of the barrel.