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The USMC M40 Sniper Rifle: At the End of a Useful Life?

The USMC M40 Sniper Rifle: At the End of a Useful Life?

Next year, the Marine Corp will celebrate the 50th birthday of an old friend: the 7.62x51mm M40 sniper rifle. Like most 49-year-olds, this old war horse 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 long range military shooting. In the post-Vietnam era, the M40A1 was cutting edge.

Early M40 sniper rifles encountered problems during the Vietnam War. Wooden stocks were susceptible to warping, and the reticle in their Redfield 3-9 Power Accurange scope could melt in high temperatures.

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 cheek piece, a 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 3-12x50. 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.

In 2009, the M40A5 made its debut featuring a suppressor-ready Schneider barrel with Surefire muzzle brake, Badger Ordnance M5 detachable magazine and a forward accessory rail for mounting an AN/PVS22 night optic. Late last year, Remington was awarded a contract to provide a folding chassis style stock that would subsequently upgrade the A5 variant to an M40A6. However, this contract has not quieted talk of replacing the platform.

It is worth noting that since the introduction of the M40A1 variant, the rifle has been accurized, fit and assembled by Marines, for Marines. Years of building M40 clones for the civilian market has given me a great respect for the level of skill and the attention to detail of the Marine gunsmiths and armorers who build these weapons in Quantico, Va. Remington has long been known for their lightweight, strong and cost-efficient Model 700. While factory Remington actions are fine for the casual whitetail hunter, the Marines use them purely as a starting point. There are many fine details that can make or break the accuracy of a bolt-action rifle, and these details are sorted out in a process called "blueprinting." A true match rifle should have the raceway of the bolt perfectly in line with the bore. The bolt face, the recoil lugs and the face of the action should be exactly 90 degrees to the bore. The internal recoil lug collar in the action should ideally have 100 percent surface contact with the recoil lugs on the bolt itself. While 100 percent contact is not always possible, I always strive to have at least 95 percent contact between the internal collar and the bolt lugs before moving forward with the build.

In the days of the M40A1, the Marines fit and installed Hart match barrels. These were replaced by Schneider stainless steel match barrels in the 1990s on the M40A3. On my personal M40 builds, I have used barrels from these companies but prefer to use a 416 stainless Krieger #18 light varmint contour with a 1:10 twist. I'm not saying that one is better than the other, but Krieger has always been my barrel of choice for long-range applications, and I am not limited by contracts and pentagon-level politics when choosing a barrel for a build. My longest shots with my personal M40A3 have been at 600m, achieving groups of under 2.5 inches using hand loads and factory match ammo. My rifle can shoot better than this; however, I cannot.

I know from personal experience how many hours can go into building one of these rifles. In recent years, the military has attempted to improve efficiency by outsourcing various armorer positions to civilians and looking to turnkey sniper platforms that are ready to hit the range the moment they arrive at the armory. There is a lot to be said for letting an extremely competent civilian company do the building and letting the Marines do the shooting. On the other side of the coin, having a weapon built by those who wear the same uniform is a tradition, a morale booster and ultimately at the end of the day brings the same confidence that an experienced skydiver has in a parachute that he packed himself.

Variants of the M40 Sniper Rifle have seen action in several U.S. conflicts since the Vietnam War, and building them to their full potential has become a proud tradition among Marine gunsmiths and armorers.

The M40 is not just a tradition for the two-man sniper team behind the rifle. It is also a tradition for the men who build it. It is the last true gunsmith's rifle in the US military. We now live it a world were firearms are assembled from parts made on sophisticated CNC machinery. The day of the hand-fit rifle is almost gone. The days of barrel chambering and single-point threading on a manual lathe are nearly behind us. Computers make calculations for us. They machine to exacting tolerances that in years past were only achieved through hours of hand fitting. While I certainly call this economic progress, it removes a human element that really only remains in one military weapon: the M40.

The human element may mean more to some than others. However, whether you are an old school shooter who prefers a hand fit weapon, or you prefer the easy to assemble, plug-and-play components of the new school era, you have most certainly heard or used the phrase "they don't make 'em like they used to." While the M40 does not involve near the labor and care taken in building a late 1800s Winchester, it is almost a perfect hybrid of old school gunsmithing paired with modern technology.

"The M40 is not just a tradition for the two-man sniper team behind the rifle. It is also a tradition for the men who build it. It is the last true gunsmith's rifle in the US military."

So here we are. Standing on the doorstep of the M40's 50th birthday party. A birthday party that questions the relevance of this half century old force multiplier. There are possible replacements knocking on the door. Knight's Armament Company's various SR25 platform rifles including the M110 Semiautomatic Sniper System (SASS) are giving the M40 a run for its money, boasting accuracy of ½ MOA using M118LR ammunition. This is effectively the same accuracy to be expected from an M40A3 or A5 using this ammo. Many of KAC's rifles weigh less than their bolt action counterparts with less overall length. Looking at the specs on paper, the question is a no brainer; the Knight's rifle is a suitable replacement. A superior, more versatile rifle in a smaller package. Another competitor is the FN MK20 SSR, which for all practical purposes is the SCAR Heavy in a DMR/sniper rifle configuration and weighs in at just over 10 pounds without an optic.

Despite competition from other semiauto platforms, the USMC's M40 Sniper Rifle remains a supremely accurate rifle. The author's own M40A3 has regularly achieved five-shot groups with .375-.400 MOA results using 168-grain match ammo.


So why has the Marine Corps not called for a direct replacement to their aging bolt-action rifle? As with any political decision, I am sure many factors come into play. I would like to think that it has something to do with their ethos that every Marine is a rifleman. The M40 is a rifleman's rifle. While 800m is the official effective range of the M40, it is easily used at distances up to 1000m, and shots significantly farther have been made. My own M40A3 regularly fires five-shot groups with .375-.400 MOA results using 168-grain match ammo. There is something about lying behind the 15-pound rifle that brings it to life like it has a story to tell. There is a certain calming effect of working the action by hand that makes the shooter one with the rifle. If the rifle could talk, I imagine it would tell its shooter to be patient, take a breath, relax, and only then to send the round.

Maybe I am a hopeless romantic stuck in the past, a dinosaur destined to be left behind. That is certainly possible. The science is stacked against the M40. The Knight's M110 is showing equal or greater muzzle velocities out of a shorter barrel. The M110 allows for faster follow up shots when life or death means hundredths of a second. The modern battlefield often does not require a ghillie suit or daylong crawls to infiltrate enemy territory, nor does it require a bolt-action rifle. The face of warfare has changed and so has the equipment. Only time will tell if we are in the last days of the M40 platform as the primary Marine Corps sniper rifle. My primary concern is not the technological aspects of the available platforms, but the corresponding psychological effect on the Marine sniper community. The M40 has long been a badge of honor for the Marine Scout Snipers. Its limited magazine capacity, manually cycled action and uncompromising performance even in the world's most inhospitable environments have always silently spoken the words "one shot, one kill." For almost 50 years, it has been the symbol of the ultimate Marine Rifleman.

In 2009, the M40A5 variant was introduced. One of its prominent new features was a suppressor-ready Schneider barrel with a Surefire muzzle brake.
In 2007, a Schmidt and Bender PM II LP 3-12x50 scope replaced the Unertl MST-100 fixed 10x scope found on previous M40A3 rifles.
Many competing rifle designs are vying to replace the M40 Sniper Rifle platform, but none yet have successfully edged the M40 completely out of service. Late last year, Remington was even awarded a contract to provide a new folding chassis-style stock to the current M40A5.
In all its various forms, the USMC M40 Sniper Rifle has seen the U.S. through a number of conflicts ranging from Desert Storm and Somalia to Operation Enduring Freedom (OEF), Operation Iraqi Freedom (OIF1) and OIF2. Whether it will continue to live on as a military sniper rifle in the future remains to be seen.
Although factory Remington 700 actions are fine in their own right, Marine armorers and gunsmiths typically use them as a starting point and build the rifles out from there. Each additional modification is aimed at gleaning as much accuracy and performance from the rifle as possible.
The M40A5 Sniper Rifle comes equipped with a suppressor-ready barrel for increased versatility.
In the post-Vietnam era, after the problems with the original M40 were addressed — such as the Redfield 3-9 power Accurange scope and the wooden stock — the newly designated M40A1 was considered cutting edge.

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