The USMC M40 Sniper Rifle: A Useful Life?

Next year, the Marine Corps will celebrate the 50th birthday of an old friend: the 7.62x51mm M40 sniper rifle. Like most 49-year-olds, this old warhorse has been through a lot. Born in the early days of the Vietnam War, the first variant was a far cry from today’s M40A5. The early models were not well suited for combat in Southeast Asia. The wooden stocks were prone to warping, and the range-finding reticle in the Redfield 3-9 power Accurange scope could melt in the hot sun. By the 1970s, these two major issues had been solved by incorporating a McMillan HTG stock and the Unertl MST-100 fixed 10x scope. Measuring 12 inches in length with a 1-inch tube, 42mm objective, and a weight of over 2 pounds, the MST-100 was compact, rugged, and reliable. These new rifles — designated M40A1 — marked the beginning of a new era in the long-range military shooting. In the post-Vietnam era, the M40A1 was cutting edge.

Having seen action in Lebanon, Grenada, Desert Storm, and Somalia, the proven M40A1 was aging. During the late ’90s, a new variant was on the rise: the M40A3. The new model utilized the McMillan A4 tactical stock with an adjustable cheekpiece, Schneider barrel, improved bedding, flush cup sling points, and, eventually in 2007, the MST-100 scope was finally replaced with a Schmidt and Bender PM II LP 3-12×50. The M40A3 has seen combat during Operation Enduring Freedom (OEF), Operation Iraqi Freedom (OIF1), and OIF2 as well as other Global War on Terror (GWOT) related hot spots around the globe.