[Have opinions on this article or equipment? Go to the Discussion
Forum to sound off.]
The race to replace the M-16/M-4 family of rifles is on -- and
Barrett has its own worthy contender in the M468 rifle, which features
an improved, more powerful 6.8mm cartridge.
The Barrett M468: Upper receiver M468/M16
conversion kit (Image from Barrett
Website).
Barrett
M468 Rifle: The Skinny
Name:
M468 Rifle (Barrett Firearms)
Type of Equipment:
Battle rifle
Killer Features:
Firepower: Rifle uses 6.8mm cartridge
which has 50% more stopping power than
the M-16's 5.56mm cartridge
Ease of adaptability: Selective Integration
Rail (S.I.R.) hand guard allows all existing
military night vision devices, combat
optics, and weapon accessories to be mounted
on rifle, without need for adjustments
For 40 years, the M-16/M-4 rifle family has reigned as the U.S. military's
standard-issue battle rifle. Any gun manufacturer that wants to tackle
that stranglehold must also take on the legacy issues that have plagued
the M-16/M-4 series over the years: maintenance and reliability issues,
overheating (especially in the M-4s), and the less than stellar stopping
power and penetrating capabilities of the Remington .223 (5.56mm
NATO) cartridge these rifles shoot.
In a previous SoldierTech article we had a sneak preview of one challenger
to the M-16/M-4's throne, the Heckler
and Koch XM-8. It did away with many of the problems noted above,
although it still uses the same Remington .223 cartridge that the
current M-16/M-4 rifle uses. That left an opening for the Murfreesboro,
Tennessee arms manufacturer, Barrett Firearms Manufacturing, Inc.
Barrett has joined the fray with the introduction of the 6.8mm M468
rifle, a sturdy challenger to the XM-8.
Barrett's aim is to eliminate the M-16/M-4's weaknesses while retaining
its strengths -- in short, improve the rifle's combat characteristics,
but also simplify operator transition to the new weapon, and reduce
maintenance and acquisition costs.
A rifle such as the M-16 can be divided into two major components:
the upper and lower receivers. The upper receiver houses all of the
firing components of the rifle: the bolt assembly, the barrel, chamber,
and the gas operating tube, as well as any iron sights or attached
optics. The lower receiver forms the "user interface" portion of the
rifle, incorporating the butt stock, magazine well, trigger assembly
and handgrip. In the M-16's case, all of its operational problems
are associated with the upper receiver. Consequentially, the Barrett
M468 is essentially a new and improved upper receiver mated to an
existing M-16/M-4 series lower receiver (there is no need to buy a
complete weapon).
Stepping Up: The Remington 6.8mm SPC (Special Purpose Cartridge)
The core component of the Barrett M468 is Remington's new 6.8mm SPC
(Special Purpose Cartridge). Indeed, the rifle's name comes from the
combination of M4 and 6.8mm. Introduced by Remington Arms in 2004,
the 6.8mm (.270 caliber) SPC is more lethal than the 5.56mm cartridge,
without a significant increase in overall bullet dimensions. Though
slightly larger than the standard M-16 cartridge (6.8x43mm as opposed
to 5.56x45mm), current issue M-16 magazines can easily be reconfigured
to accept the new cartridge. In addition, while the SPC has a slightly
lower muzzle velocity than the 5.56mm cartridge, its larger mass makes
it ballistically similar to the lighter 5.56mm round (in terms of
accuracy and bullet drop), and it delivers half again as much kinetic
energy. In real terms, this means that the 6.8mm SPC has the same
relative trajectory as the 5.56mm (which allows for the M468 to be
fired and treated essentially like a 5.56mm M-16), but with 50% more
stopping power, and a bullet speed of 2650 feet per second from a
sixteen and one-half inch barrel, delivering 1715 foot-pounds of energy,
with a six hundred meter effective range.
Must-Have
Gear
Keep It Simple
Flexibility is also the watchword with the M468, as it employs the
ARMS Inc. S.I.R. (Selective Integration Rail) hand guard, which allows
all existing military night vision devices, combat optics, and weapon
accessories (such as bipods) to be mounted on it. The SIR system not
only reduces the integration costs of the weapon (there is no need
to purchase new optics specifically tailored to the weapon), but also
gives the military the ability to selectively field the weapon and
its systems. For example, every Heckler & Koch XM-8 requires an integrated
electro-optical combat sight, whereas the Barrett M468 can be issued
as a stand-alone weapon (the SIR system comes with integrated "flip
up" style iron sights), with optional items such as the M68 CCO, PAC-4
and PEQ-2 issued to units based on their MTOE (Modified Table of Organization
and Equipment) and operational readiness level (Active Component forces
have a higher OR level than National Guard formations, for example).
The Barrett M468.
The SIR system allows for the rapid integration of the core system
(the M468) into all levels of the military, while distribution of
auxiliary systems (such as optics and night vision devices) could
be based on unit need and budgetary considerations. In addition, the
M468 should be completely adaptable (through the use of modified hand
guards) for use with existing secondary weapons, such as the M203
40mm grenade launcher (which has been a standard issue, squad level
weapon for the last 20 years) and the 12 gauge LSS under-barrel shotgun.
The ability to mount these pre-existing weapons means that new weapons
(such as the 40mm launcher that would be used with the XM-8) wouldn't
need to be purchased as additional items.
Simply put, the greatest advantage the Barrett M468 has over contenders
such as the H&K; XM-8 is improved lethality. By going to the more powerful
Remington 6.8mm SPC, Barrett has produced a rifle that is more lethal
than any other battle rifle chambered for 5.56mm NATO, yet does not
suffer from a significant loss in magazine capacity (as would have
been the case if the rifle had been chambered for the much larger
7.62mm NATO cartridge). By going to a heavier bolt carrier group and
stiffer recoil spring, Barrett has also addressed the one unresolved
legacy issue regarding the M-16s reliability under combat conditions.
These two factors, coupled with its compatibility with existing M-16
accessories and attachments, would seem to make it the hands-down
favorite to replace the M-16.
Sighting System: Folding Front Sight and Gas Block
Price: Retail Price: $2,535
Upper Conversion Kit Price: $1,494
Weight: 7.3 lbs
Muzzle Velocity: 2600 feet per second
Magazine Capacity: 5, 10 and 28 Round Magazine Configurations
Operation: Semi-Automatic, Gas Operated,
Dual Spring Extractor System, Muzzle Brake, Two-Stage
Trigger
A Matter
of Life and Death: The Virtues of 6.8mm
The 6.8mm advantage: A chart comparing
the 6.8mm cartridge with the standardissue
5.56mm cartridge (image by Barrett).
Generally speaking, armor penetration is measured
in inches (or fractions thereof) of steel plate.
Both the 5.56mm and 6.8mm cartridges mentioned in
this article won't penetrate a steel plate a quarter
of an inch thick -- think Clint Eastwood's improvised
chest plate in "A Fistful of Dollars" -- - but they
can both shoot through all non-insert body armor
types (though the 5.56 loses more energy on impact,
and is significantly less lethal). So what's the
other differences between them?
What it all boils down to is that when the 5.56mm
cartridge was first introduced to U.S. combat rifles,
it was adopted because of its size and its fit with
the U.S. "shoot-to-wound" philosophy of the time.
While the 7.62mm NATO round used in the M-14 is
much more powerful than the 5.56mm bullet, it is
also much larger; a soldier can carry twice as many
5.56mm bullets as he can 7.62mm. In extended combat
operations (wars lasting years), it was also estimated
that wounded combatants would require more logistical
support than dead ones -- with this in mind, the
U.S. adopted the 5.56 round, since if the bullet
did not kill outright, it would certainly cause
a serious enough injury that the casualty would
be hospitalized for a significant amount of time.
Unfortunately, as demonstrated by recent conflicts
such as Somalia
in 1991, the 5.56 simply lacks the "shoot-to-kill"
lethality (numerous accounts exist of Somalian insurgents
being shot repeatedly before they finally either
died or lost the will to fight) needed to stop an
attacker. This shift in philosophy (from shoot-to-wound
to shoot-to-kill) is what the 6.8mm SPC represents.
Though not much larger than the 5.56 round, it is
undeniably more lethal. The real world effect of
adopting this round can be seen how CQB (Close Quarter
Battle) is conducted. In a room-by-room fight, the
more rapidly an enemy combatant can be taken out,
the safer the operation is for friendly forces.
Since there's no time to evaluate a target's condition
in a firefight, soldiers engaged in room-by-room
combat will shoot each individual 3-5 times to ensure
that they are dead. With a heavier, more lethal
round, they need only shoot 2-3 times. While this
may not seem like a significant improvement, it
can shave valuable seconds off of engagement times
(as the shooter shifts between targets) and mean
the difference between having bullets left over
at the end of the fight -- or having to swap magazines
while surrounded by live bad guys.
Reality Check
It's clear that the Barrett M468 has a lot going for it
-- - unfortunately, its greatest advantage may also be
its undoing, at least where military use is concerned.
Because of the enormous logistical retooling involved
(in terms of manufacturing and stocking), adopting a new
cartridge for use by the armed services is a significant,
and often permanent, event (many servicemembers have aggressively,
and unsuccessfully, lobbied for the re-adoption of .45
ACP as the primary pistol cartridge since it was replaced
by the 9mm in the 1980s). The most compelling reason the
United States military will have for not adopting the
Barrett M468 is the simple fact that it currently has
millions of 5.56mm rounds on hand, and in looking for
a replacement for the M-16 the simple answer (though not
necessarily the correct one) would be to adopt a rifle
that shoots ammunition which is currently in stock and
available.
-- Eric Daniel, Military.com
What do you think about the M468? Add your own opinion
to the Discussion
Boards.
[Have opinions on this article or equipment? Go to the Discussion
Forum to sound off.]
