The Armat M42A Scope Rifle is an American-made semi-automatic sniper rifle chambered for 10mm M252 HEAP ammunition. It is employed as the primary sniper weapon of the United States Colonial Marine Corps.


Although visually very different, the M42A is designed to have a high degree of commonality with the M41A Pulse Rifle; internally, the weapon uses the same rotating breech and feed assembly, although it is chambered for slightly larger and more powerful 10×28mm Caseless ammunition.[1] The weapon's bullpup configuration gives the maximum barrel length (81 cm) while maintaining a compact profile overall. The weapon is constructed from a duratel frame covered by an titanium-aluminide casing. The rifle's stock is fully adjustable to the individual scout sniper.[1] A folding bipod is mounted above the barrel, which is free-floating and contained within a protective shroud and receiver housing. An optional flash suppressor or muzzle break can also be fitted.[1] The rifle is fed from a 15-round magazine located behind the thumbhole grip.

The rifle is a key component of battalion operations. Its long range and precision extends the tactical zone of control by up to kilometre or more, subject to local terrain. The rifle is typically issued on a scale of one per company, though it is usually reserved for use in a battalion controlled pool of up to four scout snipers.[1]


The rifle is equipped with a combined multi-spectral passive sensor scope offering twenty times magnification.[1] The scope display shows a composite image based on visual, infrared and electromagnetic emissions. The scope display can be augmented by input from the local sensor matrix via a digital comms broadcast or direct optic cable link; M314 Motion Trackers, ground radar, lidar and IR sensors may all be linked into the rifle.[1] Furthermore, the optional PARGET control system — exact details of which remain classified — is apparently able to connect the rifle into local sentry gun matrix, allowing the scout sniper to redirect sentry gun firing arcs to a desired target.[1]

Related USCMC Equipment

Scout-sniper in ghillie suit with M42A

A USCMC scout-sniper in a ghillie suit with an M42A Scope Rifle, BiMex M3 day/night goggles and portable heat sink.

Ghillie suit

Each ghillie suit is custom-made for the wearer. Beneath the natural-fiber camouflage is a suit made from radar-absorbent materials. The sniper carries an M42A scope rifle and wears BiMex M3 day/night goggles with a magnification of twenty power. The pack to his left is a portable heat sink connected by a length of superconducting cable; this optional attachment helps regulate the suits thermal signature.[2]


M252 High Explosive Armor Piercing (HEAP) round: An explosive-tipped match-standard round with a maximum effective range of 2,950 meters. Fusing is variable, and can be set to detonate either on impact or only after penetrating armor.[3] Fusing is controlled from a selector switch on the rifle.[1]

Long Range Stabilized round: An extreme-range fin-stabilized ball round with an effective range of 3,800 meters.[1]

M250 round: The M250 10×28mm Caseless round from the M56 Smartgun can also be used in the M42A without modification, although the effective range is reduced well below 2,000 meters.[1]

Behind the Scenes

Ian Mitchell (who designed the M42A for the Colonial Marines Technical Manual) said the following about designing the M42A:

"Having seen props at an ALIENS convention in 1993 especially the flamethrower I realised that each was built around a functional mechanism. Latex casts of other items, especially 1:1 scale replicas, LS Corporation and Marui provided the cool exteriors of the weapons. The flamethrower has the handguard from the M203 grenade launcher kit by LS. I also met the author of the Technical Manual, then a column in the British re-prints of the Dark Horse Aliens comics.

I studied snipers for a paper - Sniping and C3I - for a conference in 1994 at the Royal Military College of Science (RMCS), at the same time that Lee Brimmicombe-Wood wrote the book version of the Technical Manual. He asked if I would like to design a sniping weapon. M42A resulted, originally sketched during the conference in September 1994.

WA2000 seemed a sound basic shape but the function was based on the Scope. Snipers have usually had better sights and sensors than infantry so in the
Aliens universe it seemed reasonable to give them a multi-spectral capability.

American sniper rifles, such as M24 were sometimes known as Bolt Rifles, presumably because they had bolt-actions rather than the semi-automatic or fully automatic actions of M-16, M-60 and so on. Scope Rifle sounded right as the name, For designation I looked at the Pulse Rifle - the M41 and remembered the great M14 rifle. If M14 becomes M41 in the Aliens universe then M24 should become M42.

Over the last couple of weeks it has been fun using the M42C in the computer game Aliens Versus Predator. It would be great to see a real world version of the M42A!"
―Ian Mitchell on the M42A's design[4]

Note that this was posted on January 16, 2011 at 11:46 AM, around 11 months after the release of Aliens vs. Predator (which he refers to as "Aliens Versus Predator" above).





  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 Lee Brimmicombe-Wood. Aliens: Colonial Marines Technical Manual, p. 24 (2012), Titan Books.
  2. Lee Brimmicombe-Wood. Aliens: Colonial Marines Technical Manual, p. 25 (2012), Titan Books.
  3. Lee Brimmicombe-Wood. Aliens: Colonial Marines Technical Manual, p. 21 (2012), Titan Books.
  4. 4.0 4.1 " - M42a Scoped Rifle in Pulse Rifle Forum pg.5". Retrieved on 2013-09-17.


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