|
Ordnance
Notes -- by Bob Stoner GMCM (SW) Ret.
M16A1 5.56mm Rifles
 |
A
late-issue M16A1 as determined by the 30-round magazine and
enclosed flash suppressor. (Photo: US Army) |
The "Black Rifle" superseded the M14 rifle in United
States service. The original AR-15 rifle (for Armalite Rifle
Model 15) was a small caliber derivative of the Armalite 7.62mm
AR-10 rifle that had been a competitor to the M14 prior to the
latter's adoption in 1957. The AR-15 in .222 Remington came about
as a response to USAF General Curtis LeMay's call for a modern
rifle to replace the venerable M1 and M2 .30 carbines used for
Air Force Security Police.
The AR-15 capitalized on the trail blazed by the AR-10. The rifle
used aluminum for its upper and lower receivers to save weight.
It used an aluminum magazine. Its butt stock, pistol grip, and
hand guards were made of space-age plastics that were impervious
to water, chemicals, and rot. It was the antithesis of the
machined steel and wood technology represented by the M14.
Dr. Eugene Stoner, an employee of Armalite Division of Fairchild
Aircraft, demonstrated his new rifle to LeMay at an informal
shooting session using watermelons. The AR-15's effect was very
explosive as compared to the .30 carbine hits on the melons, and
LeMay was convinced: he had to have this rifle for his troops.
When the current Secretary of Defense Robert S. McNamara heard
that LeMay wanted a new rifle, he had a fit. The Army was working
on a wonder weapon called the "Special Purpose Individual
Weapon -- SPIW" which was to replace the M14. Since its
standardization in 1957, the M14 had gone through more than its
share of teething problems. Springfield Armory was the overseer
of the M14 into mass production. The first subcontractor,
Winchester Repeating Arms, had quality control and production
problems. The second subcontractor, Harrington & Richardson,
had even more problems getting rifles out the door and to the
users. The third subcontractor, Thompson-Ramo-Wooldridge (TRW,
Inc.) hit the ground running with a new plant and solved many of
the problems experienced by Springfield, Winchester, and H&R.
McNamara was not happy with the M14's tortured introduction into
service. He was also unhappy with Springfield Armory. He bet on
the SPIW as the new "wonder weapon" for DoD agencies.
The SPIW fired 13-grain darts called "flechettes") and
30mm or 40mm grenades. McNamara didn't want to be saddled with an
interim rifle in a caliber that was not DoD issue.
Program delays with the SPIW forced McNamara to reconsider his
decision, especially in light of results coming back from
"Project AGILE." Participant advisors in "Project
AGILE" took the AR-15 (now in .223 Remington caliber) into
battle in Southeast Asia. Results from the field were glowing,
especially when captured VC documents warned to beware of troops
with the "black rifle."
McNamara decided to do a "one time buy" of the AR-15
(now called the XM16) for the USAF and Army Green Berets,
Rangers, and Paratroopers. He felt it was a one-time buy because
the SPIW was just around the corner and it would replace both the
M14 and the M16. Colt Firearms of Hartford, CT was designated the
prime contractor for the new rifle. The rifle was Type
Classified as M16 by DoD, and by mid-1965 users began receiving
their first production rifles. (Three years later, when the Viet
Nam War demands outstripped Colt's production, M16s were
belatedly subcontracted to Harrington and Richardson (H&R)
and General Motor's Hydradynamic Division.)
Thanks in part to marketing hype, over enthusiastic and
exaggerated reports, and criminal bungling on the part of Army
Weapons Command, the M16 began having teething problems in the
field. Most of these problems were caused by the manner in which
the M16 was selected for service and internal turf fights within
the U.S. Army (the procuring agency).
Origins of the problems:: When the M16 went into
production, there was no technical data package available for
Colt's to build it. Consequently, tolerances tended to vary and
accumulate which, in turn, affected reliability.
Someone at DoD got the idea that the M16 did not need cleaning
after use. Part of this idea came from the kind of powder used by
the AR-15 rifles. Eugene Stoner specified the use of DuPont IMR
powders which were very clean-burning, but tended to erode
barrels faster than the Army's ball powders. The final nail in
the coffin came when the Army decided to save money by
standardizing powders between the M14 and M16 rifles. The Army
selected ball powder and this caused problems from the start.
First Problem. Ball powders of the day had a high
percentage of calcium that was left behind after firing. This
fouling tended to accumulate in and around the gas port, gas
tube, and bolt carrier key of the rifle. Fouling build-up reduced
the gas available to work the rifle's action and it failed to
function. In some cases (especially the gas tube), the fouling
could not be removed and the part had to be replaced.
Second Problem. The use of ball powders increased the
pressures at the gas port. This led to an increase in the full
automatic cyclic rate, which led to reduced part life. At one
time, it was so bad that the Army issued a deviation to its
acceptance specification that allowed Colt to test the rifle with
IMR ammunition (to pass the cyclic rate test) in order to ship
rifles.
Third Problem. Although the Army had specified the use of
chrome plating in the chambers and bores of the M14 rifle and M60
machineguns since adoption, the M16 was exempted as an economy
move. Chrome plating of the bolt and bolt carrier was also
deleted to save money and unfounded fears that the plating might
come off the plated parts and damage the aluminum receiver. The
result was that the fouling caused by the ball powders became
even harder to clean off. The heat and humidity of South East
Asia (SEA) also caused the chambers and bores to become pitted by
rust. Once a chamber became pitted, the brass cartridge case
would stick in the barrel and the bolt's extractor would tear off
the cartridge rim. A cartridge stuck in the barrel would render
the M16 useless and this problem had gotten a lot of troops
killed.
Fourth Problem. Because DoD thought the rifle required
little or no maintenance, the M16 was the only rifle ever fielded
that DID NOT have a cleaning kit issued with it. Soldiers could
not clean the rifle if they wanted to because to cleaning
materials had been procured for them! The un-cleaned rifles began
to jam and troops began to die.
Other problems. Also noted in the field were problems
with the 3-prong flash suppressor and the issued 20-round
magazine. Some troops used the 3-prong M16 flash suppressor to
break the wire bands on C-ration boxes. This bent the prongs of
the suppressor to where the severity would deflect the bullet or
blow the bullet up as it passed through the suppressor. Users
also demanded a 30-round magazine to replace the 20-round that
was current issue. This feature was to catch up to the M16s chief
rival, the AK-47, which came standard with a 30-round magazine.
By 1968, almost all of the M16s teething problems had been solved
and the rifle was reliable: bores and chambers were chromed;
cleaning kits had been issued; a new enclosed flash suppressor
was on the rifle; and training on the care and maintenance had
been done with the troops; and a product-improved M16A1 was in
the hands of the troops.
Meanwhile, Colt had marketed various derivatives of the M16 to
the DoD. One was a heavy-barreled squad automatic rifle on a
bipod for use similar to the old Browning Automatic Rifle or BAR.
The AR-15HB was not successful. A belt-fed version of the AR-15
was not successful either. A shortened carbine version called the
CAR-15 "Commando" by Colt was successful and was issued
to the DoD as the XM177, XM177E1, and XM177E2. The CAR-15 had a
telescoping butt stock; a special sound and flash suppressor; the
E1 and E2 versions had the forward assist of the M16A1; the hand
guards were shorter and round instead of triangular in
cross-section; and the barrels came in 10.5-inch and 11.5-inch
lengths (before the suppressor was added). The XM-series
"Commando" lives on in the M4 carbine (current issue to
Naval Special Warfare units).
The M16A1 soldiered into the 1970s as the standard rifle of DoD.
User complaints resulted in a product improved rifle, the M16A2.
The M16A2 was first adopted by the USMC in 1983. The new rifle
cured several problems in the M16A1: the butt stock was
lengthened; the butt stock added a storage area for cleaning
equipment; the rears of the upper and lower receivers were
strengthened; an improved front and rear sight were fitted; an
empty case deflector was added (for left hand shooters); the
ammunition was improved for better penetration (heavier bullet);
a heavier barrel was issued that had a faster rifling twist rate
to stabilize the new bullets; long, round cross-section hand
guards became standard (no more right and left sections to
match); a 3-shot burst control replaced the full automatic
function; the front receiver hinge point was beefed-up; and the
flash suppressor was redesigned to make it a compensator (to help
hold the muzzle down in automatic fire). The M16A2 is now
standard with all DoD agencies.
The M16A1 is 39 inches long and weighs 8.1 pounds. The 20-round
magazine was standard and replaced by the 30-round. The M16A2 is
40.5 inches long and weighs 8.8 pounds. The 30-round magazine is
standard.
©
2005 Bob Stoner R3
|