The Heckler & Koch XM8 is a modular assault rifle system designed by Heckler & Koch. Originally conceived as the assault rifle portion of the XM29 OICW, the XM8 was designed in 2002 as a possible replacement for the M4 carbine and M16 rifle series and is heavily based on Heckler & Koch's G36 rifle series. The XM8 is designed to be highly modular, with the ability to quickly swap parts or add attachments as the situation called for it. Prototypes were presented to the United States Army for testing in 2002. Complaints were immediately leveled at the weapon's high weight, handguard that melted under sustained fire, and low battery life of the integrated optical sight. Despite later improvements to the design, talks to procure the rifle were cancelled in 2005 for a number of reasons. The rifle still fell short of military technical requirements, and was hampered by legislation that favored American arms manufacturers and funding restrictions. Furthermore, the XM8 originally did not include Picatinny rails and is not compatible with the STANAG magazines used by the majority of US military small arms. The XM8 instead uses a proprietary attachment system known as PCAP (Picatinny Combat Attachment Points), which take the form of oval-shaped holes in the handguard.

Despite the XM8 falling out of favor with the United States, Malaysia demonstrated interest in the design and purchased a number of rifles in 2010. The XM8 is currently only in use with Malaysia's Pasukan Khas Laut (Naval Special Warfare Forces) or PASKAL. The XM8 currently in use with PASKAL is the "Spiral 3" XM8, which features a top Picatinny rail.

The Heckler & Koch XM8 and variants can be seen in the following films, television series, video games, and anime used by the following actors:

Heckler & Koch XM8 Carbine

Basic carbine variant with a 12.5 inch barrel.

Older version of Heckler & Koch XM8 - 5.56x45mm

Heckler & Koch XM8 with Insight ISM-V sight - 5.56x45mm. Note "birdcage" flash hider replacing the old "duckbill," and four PCAP accessory mounting holes added to the handguard.

Specifications

(2003-2004) (prototypes only)

Type: Assault Rifle

Caliber: 5.56x45mm NATO

Weight: 16.5 lbs (7.5 kg)

Length: 33 in (83.8 cm)

Barrel length: 12.5 in (31.8 cm)

Feed System: 30-round box mag, 100-round C-Mag drum mag

Fire Modes: Semi-Auto/Full-Auto

Film

Title	Actor	Character	Notation	Date
XXX: State of the Union	Ice Cube	Darius Stone	Dressed up G36C	2005
	John G. Connolly	Alabama Cobb
	Samuel L. Jackson	Augustus Gibbons
		Deckard's operatives
Children of Men		British soldiers	Airsoft replica	2006
District 13: Ultimatum		French soldiers	Airsoft replica	2009

Television

Title	Actor	Character	Notation	Date
Mail Call	R. Lee Ermey	Himself		2006

Video Games

Game Title	Appears as	Mods	Notation	Release Date
Söldner: Secret Wars				2004
Conflict: Global Terror	XM8 Assault Rifle / M8 Assault Rifle	w/ Heckler & Koch XM320		2005
Splinter Cell: Chaos Theory		not usable		2005
Rainbow Six: Vegas	M8	w/ various attachments	Malaysian version	2006
Splinter Cell: Double Agent			not usable	2006
Ghost Recon Advanced Warfighter	M8	w/ optional Heckler & Koch XM320		2006
Alliance of Valiant Arms				2007
Crysis	SCAR	w/ various attachments		2007
Ghost Recon Advanced Warfighter 2	M8	w/ optional Heckler & Koch XM320	PC only	2007
Soldier of Fortune: Payback		w/ various attachments	usable in PS3 and X360 versions	2007
Cross Fire	"XM8"			2007
Command & Conquer: Red Alert 3			seen in intro cinematic	2008
Combat Arms	XM8		EU version only	2008
Rainbow Six: Vegas 2	M8	w/ various attachments	Malaysian version	2008
Metal Gear Solid 4: Guns of the Patriots	XM8	w/ Heckler & Koch XM320		2008
Counter-Strike Online				2008
Saints Row 2	AR-50 XMAC			2008
Battlefield: Bad Company	XM8	w/ Heckler & Koch XM320		2008
Mercenaries 2: World in Flames	Combat Rifle		w/ 40-round capacity	2008
ArmA II				2009
The House of the Dead: Overkill	Assault Rifle			2009
Alpha Protocol			not usable	2010
Battlefield: Bad Company 2	XM8	w/ Heckler & Koch XM320		2010
Shadow Harvest: Phantom Ops	XM8		early version	2011
Battlefield Play4Free			With optics replaced with iron sights or optional EOTech or Sightmark Sure Shot red dot sight	2011
Crysis 2	SCAR	w/ various attachments	w/ Remington ACR elements	2011
Call of Duty: Black Ops 2	M8A1	w/ rail system and various attachments		2012
Warface		w/ various attachments		2013
Sniper: Ghost Warrior 2			used by guards	2013
State of Decay	"XM8"	with Insight ISM-V sight	added in Lifeline DLC (2014)	2013
S.T.A.L.K.E.R.: Misery				2018
Battlefield 2042				2021
S.T.A.L.K.E.R. GAMMA				2022

Anime

Title	Character	Mods	Notation	Release Date
Rideback	GGP forces			2006

Heckler & Koch XM8 Compact Carbine

Heckler & Koch XM8 Compact Carbine - 5.56x45mm

Heckler & Koch XM8 Compact Carbine with full stock - 5.56x45mm

Compact assault rifle variant with a 9 inch barrel and collapsible stock, intended for use as a personal defense weapon.