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M-16A2

  • Introduction – The M16 rifle and all its present day variations are in service with practically every military and law enforcement agency. Its reliability, ease of use, accuracy and seemingly unlimited supply of tactical accessories have made it the weapon of choice for over 60+ countries. The M16A2 rifle system consists of a rifle, magazine, and a sling. It is a lightweight, gas operated, air cooled, magazine fed, shoulder fired weapon that can be fired either in automatic three round bursts or in semiautomatic single shots.
  • Features / Specifications -
    • Manufacturer – Colt Manufacturing and Fabrique Nationale Manufacturing Inc
    • Caliber – 5.56mm
    • Weight – w/30 round magazine is 8.79lbs
    • Length – Rifle w/compensator is 39 5/8 inches (excluding M4s)
    • Mechanical Features – Rifling is a Right Hand 1/7 twist
    • Muzzle Velocity – 3100 fps
    • Cyclic rate of Fire – 800 Rounds per minute
    • Max Effective Rate of Fire – Semi (45 rpm), Burst (90 rpm)
    • Sustained Rate of Fire – 12/15 rpm
    • Max Effective Range – 550 Meters (Point Target), 800 Meters (Area Target such as a vehicle)
    • Max Range – 3534 Meter
  • Why the M16? – Conflicts leading up to and including Vietnam resulted in a growing dissatisfaction with the M14. Numerous studies led the Army to the development of a light weight weapon capable of firing a burst of bullets with controlled dispersion. The Army Ordinance Corp initially disliked the AR-15/M16. However, the Armalite AR-15 was still adopted by the Secretary of Defense as the 5.56mm M16 rifle. The M16 was capable of firing in a semiautomatic or fully automatic fire mode. The M16 was originally developed to have the same effective range as the M14 rifle it replaced, but it was most effective at a range of 215 yards (200m) or less. The M16 used a 5.56mm (.223 cal.) cartridge in 20- or 30-round magazines. There were a number of problems encountered during initial fielding, but better training, preventive maintenance, and after several design changes, the weapon became the standard issue rifle of the US Army , with some 3,690,000 manufactured.
    The M16A2 semiautomatic rifle is the standard by which all military rifles of the future will be judged. This variant of the M16 fires a three-round burst in the semiautomatic mode. The rifle system incorporates an adjustable rear sight which corrects for both windage and elevation, a heavier barrel with 1-in-7 rifling, and a muzzle compensator to prevent muzzle climb during semiautomatic operation. This was particularly effective at controlling the dispersion of the three round burst. The M16A2 is capable of firing all NATO standard 5.56mm ammunition and can fire 40mm grenades when equipped with the M203 Grenade Launcher.
  • The M4 CarbineThe M4 5.56mm Carbine is a lightweight, gas operated, air cooled, magazine fed, selective rate, shoulder fired weapon with a collapsible stock. A shortened variant of the M16A2 rifle, the M4 provides the individual soldier operating in close quarters the capability to engage targets at extended range with accurate, lethal fire. The M4 Carbine achieves over 80% commonality with the M16A2 Rifle and will replace all M3 .45 caliber submachine guns and selected M9 pistols and M16 rifle series. The weapon is the standard rifle of issue for Light Infantry Units to include Airborne, Ranger and Special Forces units.
  • Improvements over the M16A1 –

    • a heavier, stiffer barrel than the barrel of the M16A1

    • a redesigned handguard, using two identical halves, with a round contour which is sturdier and provides a better grip when holding the rifle

    • new buttstock and pistol grip made of a tougher injection moldable plastic that provides much greater resistance to breakage

    • an improved rear sight which can be easily adjusted for windage and range

    • a modified upper receiver design to deflect ejected cartridges, and preclude the possibility of the ejected cartridges hitting the face of a left-handed firer

    • a burst control device, that limits the number of rounds fired in the automatic mode to three per trigger pull, which increases accuracy while reducing ammunition expenditure

    • a muzzle compensator, designed to reduce position disclosure and improve controllability and accuracy in both burst and rapid semi-automatic fire

    • a heavier barrel with a 1 in 7 twist to fire NATO standard SS 109 type (M855) ammunition which is also fired from the M249 Squad Automatic Weapon (SAW). This further increases the effective range and penetration of the rifle cartridge. The M16A2 will also shoot the older M193 ammunition designed for a 1 in 12 twist.

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    Modern sniper rifles

    Modern sniper rifles
    last updated: 26 jan 2001

    The main purpose of the sniper rifle is to destroy valuable targets at
    extended ranges with aimed fire, and with as few ammunition
    as possible. In most cases, “the target” means the human being (enemy
    soldier, armed criminal, terrorist, president etc.), and
    the “as few ammunition as possible” often means “one shot”. The range for
    sniper fire may vary from 100 meters or even less
    in police/counter-terror scenarios, or up to 1 kilometer or more – in
    military or special operations scenarios.
    Some sniper rifles, mostly – large caliber ones, used also as anti-material
     weapons, to destroy, or, more often, render
    unusable or unoperable, targets such as radar cabins, jeeps, parked
    aircrafts etc.

    History of sharp-shooting traces its ancestry well back into XIX or even
    into XVIII centuries. Early sniper rifles were standart
     issue army rifles, selected for accuracy, or privately purchased
    commercial target or hunting rifles. During WW I and WW II
    both sides used a lot of general issue bolt action rifles (such a
    Russian/Soviet Mosin M1991/30, US M1903A4, British SMLE
    No.4(t), German G98k etc.) fitted with some kind of telescopic sight. Some
    of general issued semi-auto rifles also were used
    in sniper role, such as Soviet SVT-40 and US M1 Garand.

    bolt action rifle topped with powerful scope for long-range shots The
    practice of developing the military sniper rifles from
    standart issue firearms is still used in many countries. Ususally,
    manufacturer or special military unit select some rifles for
    their better-than-average accuracy, then adopt these rifles for sniper role
     (i.e. convert them from select-fire into semi-autos,
    add ajustable stocks, bipods, scope mounts etc.). Many of military sniper
    rifles, discontinued in service or currently in use,
    such as US M21, German G3-ZF and G3-SG/1, were made that way.

    Some sniper weapons were made for marksmen use from the scratch, because
    the clients wanted some special
    characteristics, that were unavailable in any service or commercial
    weapons. One such example – Soviet SVD Dragunov
    rifle. It was designed on Soviet Army request as a lightweight, powerful
    and reliable semi-auto rifle, and remains in service
    for almost 40 years.

    But wast majority of sniper rifles, especially – police ones, were designed
     on existing commercially available hunting
    or sporting rifles. The best examples – the US military sniper rifles M24
    and M40, along with many custom police rifles,
    were (and still are) built on Remington 700 actions, available for general
    public in many hunting and target rifles. Famous
    SIG-Sauer sniper ifles also buil on their (SIG or Sauer) hunting rifles.
    Some sniper rifles, mostly also police ones, designed
    on target/sporting rifles. To name few: Blaser R93 Tactical (Germany),
    Sv-98 and MC-116 (Russia).

    In general, all sniper rifles may be rougly separated into 3 major
    categories: Miltary sniper rifles, Police/Law Enforcement
    tactical/sniper rifles, and Special purpose sniper rifles.

    Military sniper with it’s gear and camo suit Military sniper rifles used by
     different military units. Along with main requirements
     for accuracy and sufficient effective range, military use commands some
    other: military sniper rifle must not be too heavy,
    because sniper usually must carry it for the long hours, with ammunition
    and other stuff. Also, military sniper rifle must be
    extremely reliable in any weather and climatic conditions and could
    withstand hundreds of rounds fired without cleaning
    and maintenance and without any loss of accuracy. Third, military sniper
    rifle must be easy to fieldstrip and easy to repair
    in field conditions. Also, military sniper rifle often must have backup
    iron sights, in case of telescope breackage.
    Another requrement is that military sniper rifle must use military
    ammunition, conforming to international war threaties and
    generally available to the troops. In most cases, military sniper rifle use
     variants of the standart caliber army cartridges
    (such as 7.62mm NATO or 7.62x54mm R), specially developed for sniping.
    Effective range for the standart-caliber sniper rifles against the single
    human-sized target may be estimated as 700-800
    meters for first-shot kills. To extend effective range beyond 1000 meters,
    often used sniper rifles, designed to fire more
    powerful ammunition, such as .300 Winchester magnum (7.62x67mm) or .338
    Lapua magnum (8.6x70mm).
    Military sniper rifles may be further separated in two tactically diffrent
    categories: the sniper rifles itself, designed to
    achieve aimed hits at long distances, and the Designated Marksman Rifles
    (DMR), designed to provide accurate fire
    support for line troops. While the “true” sniper rifles usually are bolt
    action ones, to achieve maximum accuracy, the
    DMRs usually are semi-autos, such as Russian SVD or German G3ZF or MSG-90,
    to gain higher rate of fire. But the
    difference lays more in tactical applianses, than in the rifles itself.

    Police / Law Enforcement (LE) sniper rifles are somewhat another kind of
    tools. If in most military/war scenarios wounded
    enemy is equivalent to killed enemy, or even better, in LE and
    counter-terror (CT) scenarios wounded criminal or terrorist
    may lead to many innocent wictims. Sometimes, the LE or CT sniper must not
    only kill the terrorist, but hit the particular part
    of the body – head, or hand, holding the gun, etc. So, in general, LE and
    CT sniper rifles require more accuracy, but at
    shorter distances. The majority of LE or CT scenarios require precision
    shooting at the distances lesser that 300, or even
    100 meters. These scenarios also require really few shots per scenario -
    sometimes one and the only one shot. This also
    require extreme accuracy and stability of results in any weather
    conditions. LE and CT snipers also has no limitations on
    caliber and ammunition selection, so they could select almost any
    caliber/cartridge they department want, or can afford.
    Usually, LE/CT sniper rifles had completely ajustable stocks to suit
    snipers of different statute, sometimes they got
    half-of-dozen ajustable screws. This is absolutely unsuitable for military
    sniper rifles, but for LE sniper rifles, which are
    usually carried to the point of action in special cases, this is OK.
    Many USA made LE sniper rifles are built on the hunting “varmint” rifles.
    Varmint rifles are small or medium caliber
    hunting rifles, designed to kill small pests, such as squirrels, rabbits
    etc., at extended distances. Some LE sniper rifles,
    such as Remington 700 Police, are simply Remington 700VS varmint hunting
    rifle barreled actions, bedded into
    sniper-style stocks.
    In Europe, some sniper rifles built on sniper rifles (such as Mauser 66,
    SIG-Sauer SSG2000, Blaser R93 Tactical), and
    some built on hunting rifles (such as Steyr Scout Tactical). LE/CT sniper
    rifles use many kinds of ammunition, from .22LR
    for training and short-range sniping, to .308 Win, 6.5x55mm, .300 Win
    magnum etc.

    Special Purpose sniper rifles may be, in turn, splitted into 2
    sub-categories:
    Large-caliber rifles for ulra-long range sniping and ani-material use, and
    silenced rifles for covert operations.
    Large caiber sniper rifles usually built to use heavy machineguns
    ammunition, such as .50BMG (12.7x99mm) or 12.7x108mm.
    Effective range of such rifles is up to 1500 meters and above, depending on
     size of target and quality of the ammunition.
    General purpose machinegun ammo usually produced not-too-good accuracy, but
     recently some special “sniper”
    rounds developed in .50BMG caliber.
    Silenced sniper rifles usually are used with special sub-sonic ammunition
    and removable or integral silencers to produce
    lower sound report. Sub-sonic ammo decreases effective range down to
    300-400 meters, but it’s worth. With the correct
    ammo and silencer, the sound of the gunshot could be easily mised
    completely at the distances of 100-200 meters at night,
    or even at 30-50 meters – in daily urban noize.

    Sniper rifle Accuracy
    The most common way of describing the accuracy of the sniper rifle is to
    measure average diameter of the circle, that
    may be drawn arount the group of bullet holes in the target. Usually, the
    rifle is fired from the rest with groups of the 5 (or 3)
    rounds, and then every group is measured. Average group diameter is the
    most common criteria of rifle accuracy.
    Today, the thin line between “good” and “poor” accuracy is usually laid in
    1MOA group. 1 MOA (Minute Of Angle) is
    measure of the angle, that formed with the triangle with muzzle as the top
    and the group as the base. 1 MOA is roughly
    equivalent to 1 inch group diameter at 100 yards (91 meter), or to 2 inches
     at 200 yards etc. So, if you read that rifle XXXX
    shooths 1MOA groups, it means that at 300 yards this rifle could place 5 or
     so bullets in circle of no more than 3 inches in
    diameter. Many modern sniper rifles, when loaded with right ammunition,
    could shoot 0.5MOA, or even 0.3MOA, which
    mean 1 inch groups at 300 yards, or 2 inch (50 millimeters!) groups at 600
    yards (550 meters).

    (c) Max Popenker, 2001

    Comments (1)

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