M16A2 5.56 mm Rifle

The M16A2 rifle is a 5.56mm, magazine-fed, gas-operated, air-cooled, shoulder-fired weapon that can be fired either in automatic three-round bursts or semiautomatic single shots as determined by  the position of the selector switch.

• The upper receiver and barrel assembly has fully adjustable rear and front sights and a compensator that helps keep the muzzle down during firing. 

• A rubber pad mounted on the butt stock and a buffer assembly inside the butt stock helps absorb the recoil when fired. 

• The barrel is surrounded by two aluminum lined Fiberglass hand guards which are notched to permit air to circulate and cool the barrel and also protect the gas tube. 

• A bayonet and/or bipod can be attached to the barrel of this weapon individually or at the same time.

Right Side of Rifle

Left Side of Rifle

To Load:

• Point the rifle in a safe direction.
• Take a loaded magazine and shove it firmly into the weapon until you hear a "click."
• Tug downward on the magazine to make sure it is completely engaged and does not pull out of the weapon.
• Pull the "Charging Handle" straight back until it won't go any further, then release it. It will spring back to its' original position, cocking the internal hammer and bringing a cartridge into the firing chamber. The weapon is now loaded and will fire if you pull the trigger.
• If you do not intend to fire the weapon immediately, move the "Selector Lever" switch from "Semi" or "Burst" to "Safe," and close the "Ejection Port Cover."

To Fire:

• Aim a loaded rifle at the target.
• Using your thumb, move the "Selector Lever" from "Safe" to "Semi" or "Burst."
• Squeeze the trigger and the weapon will fire.
• If you have the "Selector Lever" on "Semi," you will fire a single round. If it is on "Burst," the rifle will automatically fire three rounds in a burst.
• In either case, you can continue pulling the trigger and each time, the trigger pull will fire the rifle, and the gasses from the bullet will cause the rifle to eject the empty cartridge and bring a new cartridge into the firing chamber.
• You don't have to worry about the "Ejection Port Cover" being open or closed. If it is closed and the weapon wants to eject a cartridge, the Ejection Port Cover will be automatically forced open and will remain open until you decide to close it.

To Unload:

• Point the rifle in a safe direction.
• Attempt to move the "Selector Lever" to "Safe." 
• Using your right index finger, depress the "Magazine Release Catch" just above the trigger guard on the right side of the rifle, and then remove the magazine from the weapon. (They often just fall out as soon as you press the release catch.
• After the magazine is removed, pull straight back on the "Charging Handle" to eject any round from the firing chamber. 
• Look through the ejection port to visually confirm that there is no cartridge in the firing chamber. Then release the Charging Handle and let it spring forward to its' normal position.
• Place the "Selector Lever" to "Safe."
• Close the "Ejection Port Cover."

Clearing the Rifle:

• Clearing a weapon means unloading the it and leaving it in a status that it is visually obvious to anyone who sees it that it is empty and temporarily disabled.
• To clear the M16A2 rifle, remove the magazine, pull the "Charging Handle" backward and lock in the open position, move the "Selector Lever" to "Safe" and leave the "Ejection Port Cover" open. This is the safest way to leave the weapon.

Helpful Tips in Using this Weapon

• Although the projectile will travel up to two miles, its' maximum effective range is about 300 meters, in practiced hands, in daylight, with a stationary, man-sized target. Most medical personnel won't be able to achieve those results, so try to hold your fire 'til you "see the whites of their eyes."
• Effective rifle fire, other than at point blank range, requires careful sighting (aligning the front and rear sights with the target), breath control (try not to breath while firing), a smooth, steady trigger pull (try to avoid jerking the trigger), and avoidance of "flinching" in anticipation of the weapon firing. The latter can be avoided through practicing "dry fire" techniques.
• In the event of a misfire, try the Slap, Rack, Bang procedure:
  • Slap the magazine upward to more firmly seat it in the weapon.
  • Rack back the "Charging Handle" and release it, ejecting the misfired round and bringing a fresh round into the firing chamber. Let the the "Charging Handle" spring back on its' own...don't "ride" it back.
  • Bang goes the rifle when you pull the trigger.
• When defending against multiple targets, try to stop the most threatening target first. Usually that is the target closest to you. However, someone with an automatic weapon or shotgun is more dangerous to you and your patients than someone with a pistol. Likewise, someone with a rifle is more dangerous than someone with a pistol.
• Take advantage of any cover you may have. Crouching behind a rock or packing crate is much better than standing out in the open. If you are caught out in the open, quickly make a decision to either go to the ground, or to run to cover. If you go to ground, keep moving (rolling, crawling), to decrease the chance of your being wounded.
• Should you become wounded, keep shooting. The best defense against incoming fire is to return fire, wounded or not.

For additional information, read:

M16A2 Assault Rifle Familiarization, FMSS Class 0210

FM 21-75: Combat Skills of the Soldier

Emergency War Surgery NATO Handbook: Part I: Types of Wounds and Injuries: Chapter II: Missile-Caused Wounds: Projectiles

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*This web version is provided by The Brookside Associates, LLC.  It contains original contents from the official US Navy NAVMED P-5139, but has been reformatted for web access and includes advertising and links that were not present in the original version. The medical information presented was reviewed and felt to be accurate in 2001. Medical knowledge and practice methods may have changed since that time. Some links may no longer be active. This web version has not been approved by the Department of the Navy or the Department of Defense. The presence of any advertising on these pages does not constitute an endorsement of that product or service by either the US Department of Defense or the Brookside Associates. The Brookside Associates is a private organization, not affiliated with the United States Department of Defense.

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