Watervliet’s revolutionary process lightens the load for US soldiers


The Watervliet Arsenal in New York has released this week its first shipment of redesigned 60mm lightweight mortar barrels that are part of a new U.S. Army contract valued at more than US$9.5 million.

These new mortar systems are up to 20 percent lighter than the previous versions and this is the first major redesign of the widely used infantry mortar system since the late 1970s, says Colonel Mark F. Migaleddi, the Arsenal commander. “What we have been able to achieve by using advanced manufacturing techniques to machine a new materiel called Inconel was to help lower the weight of the 60mm mortar system by about nine pounds,” Migaleddi said.

After years of process refining and development, Migaleddi announced earlier this month that a revolutionary “flowform” manufacturing process is now a reality at the Arsenal. “Because the flowform process uses cold forging versus heat forging, we are able to forge lighter weight Inconel barrels,” Migaleddi said.

According to the Army’s Program Executive Office for Ammunition, the Army’s first M224A1 60mm Lightweight Company Mortar Systems were tested in June by the 1st Special Forces Group at Fort Lewis, Wash., to great success. The average load for a 60mm assistant gunner is 122 pounds and so, reducing the weight of the mortar system by more than nine pounds has proven in testing to not only reduce crew fatigue, but has also reduced crewmen’s movement time over a cross-country course, said Peter Burke, PEO Ammunition’s deputy product manager for Guided Munitions and Mortar Systems.

The 60mm mortar system is used primarily by the infantry as an indirect fire weapon when a high angle trajectory is required to hit enemy troops, materiel, and positions. The new mortar system will fire the same family of munitions as the previous model and at the same rate of fire.

The Army will replace all of its 1550 60mm mortar systems and the Arsenal’s share of this fleet-wide replacement program is about 500 mortar barrel assemblies. The Arsenal’s contract runs through fiscal year 2013.

The Arsenal’s business model has changed in recent years from a focus on cannon production to the production of mortar systems due to the type of ground combat that the US military is doing in Afghanistan. During the past year, the Arsenal has manufactured various parts — such as tubes, leg assemblies, and base plates — for more than 2000 mortar systems for the US Army and Marine Corps.

According to Tom Pond, the Arsenal’s current director of operations, the Army’s Benet Laboratories also deserves must praise in the research and development of this new manufacturing process. Benet Labs is a premier military weapons research and design facility located on the Arsenal.
“This was truly one of those projects where Benet engineers walked across the street and spent a significant amount of time with the machinists,” Pond said. “You can’t beat having the designer of the system and the manufacturer of the product within the same fence line.”