XM29 Integrated Air Burst Weapon
Objective Individual Combat Weapon (OICW) Increment 3

The Objective Individual Combat Weapon (OICW) was intended to be the lethality element of the Objective Force Warrior program and also to be used as the lethality element of the Land Warrior proram. It was also planned to be fielded as a stand-alone system. The OICW, designated as XM29 by the US Army, was a developmental infantry weapon system that was expected to revolutionize the close combat fight by substantially improving the infantry soldier's effectiveness. The XM29's unique, full-solution target acquisition/fire control system combined with precision 20mm air bursting ammunition would provide a significant overmatch capability against a variety of threats, resulting in a dramatic increase in soldier survivability. The XM29 was one of the premier programs within the new Program Manager Soldier Weapons Office in the Program Executive Office Soldier Systems until 2005.

The XM29, developed by Alliant Techsystems Integrated Defense (ATK) and Heckler and Koch, fired special air-bursting projectiles and standard 5.56mm ammunition. As of 2005 the XM29 was still still too heavy and unwieldy for Army requirements. Instead of scrapping the XM29, however, the Army decided to perfect each of XM29's components separately, so soldiers could take advantage of new technology sooner. The parts would be brought back together when lighter materials become available. At that time, the XM29, which became termed as OCIW's Increment 3, was shelved until the 5.56mm component (Increment 1) and the air-bursting component (Increment 2) were perfected. As of 2011, while the Increment 2 system had been fielded, the results of the Increment 1 development were unclear.

XM29 was to be an integral part of the Land Warrior system and, as such, would provide a tremendous enhancement in tactical and operational capability when fielded. The XM29 was also planned for introduction into the Objective Force as an individual system for both the Future Combat Soldier and the Objective Force Warrior. In the Objective Force, it would be linked to a networked battlefield environment, further benefiting the overall force capability.

The XM29 had a dual semi-automatic over and under configuration capable of firing 20mm high-explosive air-bursting (HEAB) ammunition or NATO standard kinetic energy 5.56mm ammunition. Both weapons were magazine-fed, providing the combat soldier an operational firepower advantage over existing single shot systems. The full-solution target acquisition fire control system had a laser range finder, direct view optics, integrated thermal imager, ballistic computer, fuze setter, environmental sensors, and compass. The precision 20mm ammunition included HEAB and Target Practice (TP) variants. The system had been demonstrated at ranges 2 to 3 times the existing 40x46mm system to accurately deliver an air burst one meter over the lased target on the first shot fired.

While an M16 cost under $1,000, OICW might cost $10,000. That was because OICW was a single system consisting of a fire control system and combinatorial weapon. The functions contained within the system included the "add-ons" used on the M16 or M4 such as optics, thermal weapon system, and aim light. With these functional add-ons, the existing M16/M4/M203 system cost exceeded $35,000 each.

The XM29 program focused on verifying system safety and launching into the full scale engineering design of the weapon, fire control, and ammunition. The XM29 demonstrated the integrated system capability "end to end" on three different test sequences over the multiple phases of the program. These results validated that it was technically low risk to field this leap-ahead capability in shoulder-fired HEAB ammunition.

The target acquisition/fire control system was upgraded, primarily focusing on reducing weight by integrating the latest laser, sensor, optics, electronics, and material technologies. It incorporated improved, low-weight optics for daylight viewing and integrated thermal optics for use at night. As the lethal element of the Land Warrior, it had been designed to integrate with other Land Warrior systems, allowing the XM29 to communicate from the fire control system to the Land Warrior heads-up display and also to accommodate power sharing between systems.

The weapon was also being upgraded with a focus on weight reduction and ruggedization. Weight optimization was the primary driver for every weapon piece part and component. The program team was evaluating alternate weapon operating principles that supported weight reduction. Additional enhancements were also being made to ensure ruggedness and boresight retention between the 5.56mm barrel, 20mm barrel, and fire control.

As of 2002, initial fielding of the XM29 was scheduled for GFY08. The XM29 program had implemented a block upgrade or "evolutionary" approach to fielding the weapon system. This encompassed an "initial fielding" of a "Block 1" system, which was designed to enable insertion of future technology enhancements. This approach would expedite completion and qualification of the initial Block 1 design, while preplanning future upgrades, such as advances in sensors and electronics technologies, MEMS fuze elements, advanced composites and materials, fuel cells, nano-technologies, ceramic gun barrels, wireless connectors, and future digital technology. These enhancements would help further reduce system weight, increase lethality, improve ruggedness, and increase system reliability and effectiveness beyond the Block 1 design. As of 2002, the XM29 project schedule was aligned so the First Unit Equipped (FUE) supported the fielding of the Future Combat System (FCS). This positioned the Block 1 XM29 FUE in GFY08. The OICW would not replace all of the M16 and M4. The existing US Army Basis of Issue (BOI) was 4 OICW weapon systems per 9-man squad.

Alliant Techsystems Integrated Defense (ATK) of Plymouth, Minnesota was the XM29 system integrator and provider of the 20mm HEAB ammunition. Brashear, LP of Pittsburgh, Pennsylvania was responsible for the target acquisition and fire control. Heckler and Koch of Germany was the weapon system developer and manufacturer. Omega of Columbus, Georgia was responsible for training concept planning. This integrated team worked together for several years, bringing the system through the concept development and proof of principle phases into the current system development phase. The program successfully passed the Milestone 1A decision, clearing the path for final development and fabrication of the initial Block 1 weapon system in 2002.

By late 2003, the XM29's development was progressing, but it was overweight and years behind schedule. Originally, the weapon was supposed to begin production in 2005, but that date had been pushed back to the end of FY10. Designers struggled with the air-burst munition, and fought to reduce the weapon's weight. The original prototype of the XM29 weighed 18 pounds, which Army officials said was too heavy. By 2010, plans called for the weight to drop to 15.5 pounds, up from an initial goal of 14 pounds.

The XM29 Integrated Air Burst Weapon was expected to replace selected M16 rifles and M4 carbines. The modular, dual-barrel XM29 would combine the lethality of the 25mm family of munitions (which replaced the 20mm ammunition in 2004) and 5.56mm NATO ammunition with a full-solution fire control system to effect decisively violent and suppressive target results and to greatly improve small arms performance. This fire control system would incorporate a laser rangefinder, ballistic processor, direct view optics, electronic compass (bearing, tilt, and cant), thermal sighting, and an internal display. The XM29's precision airbursting 25mm ammunition was capable of defeating not only exposed targets, but those in defilade (targets that have taken cover behind structures, terrain features, and/or vehicles), a capability lacking in existing direct fire rifles and carbines.

The XM29 would provide an overmatch in system effectiveness while increasing its ability in providing effective day/night operation. It would provide a significant increase in lethality for a basis of issue of 4 XM29s per infantry squad. It would mitigate the aim error associated with standard KE ammunition by providing the option of firing a 25mm air-bursting projectile with a low-arc trajectory.

In July 2004, it was decided to speed up development of its components as separate weapons, instead of developing the XM29 gradually. The XM8 lightweight carbine was to form the basis for the rifle portion, designated as Increment 1, and the grenade launcher would become the XM25 Air Burst Weapon, designated as Increment 2. In addition, it was decided tha the XM25 would fire a 25mm air-bursting munition, rather than the 20mm planned for the XM29. Development of the complete XM29 (Increment 3) system was shelved, and would be resumed once the OICW Increment 1 and 2 components were developed, and weight constraints of entire system were met.

The XM29 would be compatible with the digital battlefield and would provide the lethality upgrade for the Objective Force Warrior. Spiral Development was being used to accelerate the fielding of both weapon subsystems separately in advance of the dual-barrel system. The XM25 was the stand-alone component that provided the airbursting performance and the XM8 was derived from the KE component of the XM29. As of 2004, the XM8 was undergoing accelerated development to allow early fielding to replace M4 carbines and M16 rifles. It was hoped that such fielding would occur in 2005.