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8.
Semiautomatic version of the M-16 used by the United States military, legal for civilian ownership in most states thereof. Uses the .223/5.56 NATO round. Like the M-16, it's accurate but not very reliable because of its direct gas impingement system.
My buddy got killed by home invaders because his AR-15 jammed. He should have bought an AK or FAL.
by epsilon minus January 18, 2004
 
1.
The AR-15 is a common assualt rifle. Very similar in looks to an M-16, but not exactly.

AR does NOT stand for Assault Rifle, as is commonly believed. AR stands for the original company that manufactured it, ArmaLite. ArmaLite sold their rights to the AR-10 and AR-15 designs in 1959 to Colt.

With a simple barrel and receiver switch, this rifle can fire 14 different calibers and sizes of ammunition, ranging from .22LR to .50BMG.

Completely customizable, this rifle can also be a personal defense firearm at less than 36 inches long, to a sniper rifle over 50 inches.

Standard magazine (or clip, if you prefer) is 30 rounds, but aftermarket 5, 10, 20, 30, 40, 60, 90, and 100 round magazines are available as well, but only the 5 round, non-detachable clip is legal in California. These clips are breech loaded, and do NOT come off. The reason for this is because of the Assault Weapon Ban that The Clinton Administration put into affect, and this method of semi-automatic action slows the loading process and is supposed to reduce murders. All it did was boost illegal weapon sales.

With the modular accessory rail, hundreds of different aftermarket accessories are available. These range from simple, and relatively cheap in price, tac-lights, vertical secondary pistol grips,to night-sights, to bipods, to thermal scopes, to night-vision scopes and infrared scopes beyond normal mag-scopes with somewhere around 20+ compatible scopes. Other accessories are different stocks, from collapsibles to solid body, to skeleton, to adjustables.

These rifles, when sighted in are accurate up to 500 yards, with a range well beyond that.

The semi-automatic feed uses a direct gas impingement system. (If lost with this term, use wiki)

This rifle was designed by Eugene Stoner in 1958 as an updated, lighter version of the AR-10. The design was initially submitted as a new rifle for the US Armed Forces, and is what the M-16 was based off of.

Overall, this is a very effective weapon for home defense, hunting, sharpshooting, and just fun at the range.
Possible calibers for the AR-15 are:

.223REM
5.56x45mm NATO
(Yes, the NATO round is different from a .223REM. The NATO round has higher power, and needs mods to the weapon to be fired safely. Commonly confused and called the same as .223REM, because they have the same physical dimensions but different power levels)
.22LR
6.5 Grendel
6.8SPC
.45 Bushmaster
.300 Whisper
.458SOCOM
9mm Parabellum
7.62x39mm
.50AE
.50 Beowulf
.50BMG
(All these .50s are different power ratings and dimensions, but the bullet itself is the same size.)
.45ACP
by Brian Keeney November 09, 2006
 
2.
The AR-15 is the semiautomatic version of the M16 series of assault rifles, designed by the great designer Eugene Stoner, and it is most commonly used by the US armed forces. I would get into the history of this gun, but it is very longwinded but thoroughly interesting. AR-15s are usually chambered in 5.56 x 45mm (.223 Remington) caliber and have either 24", 20", 16", or 11.5" barrels and have either collapsible stocks or full stocks and may either have a NATO railed flattop or a carrt handle with an adjustable rear sight. This weapon has been the basis of numerous high-accuracy rifles.
I am so getting an AR-15 when I get my license.
by Ian R May 14, 2005
 
3.
AR does NOT stand for Assault Rifle
50 Cent "Wanksta"

"what you know about AKs and AR-15s?"
by CubaGT February 12, 2007
 
4.
a very powerfull, semi-automatic, civilian version of the US Army's M16. Legal to own in most states execpt CA. A good gun
by schulte November 07, 2003
 
5.
An assault rifle most commonly used by Law Enforcement and Military. The AR15 uses the .223 Caliber (NATO 5.56).
During the North Hollywood shoot-out between the two gunmen armed with AK-47s and Body Armour. The LAPD had no tactical advantage against the two gunmen with their puny ass 9mm pistols. They went to a local gunshop and snagged some AR15s and shot the gunmen down since their body armour couldn't stop it.
by dR-Jester August 28, 2003
 
6.
The AR-15 is a common assualt rifle. Very similar in looks to an M-16, but not exactly.

AR does NOT stand for Assault Rifle, as is commonly believed. AR stands for the original company that manufactured it, ArmaLite. ArmaLite sold their rights to the AR-10 and AR-15 designs in 1959 to Colt.

With a simple barrel and receiver switch, this rifle can fire 14 different calibers and sizes of ammunition, ranging from .22LR to .50BMG.

Completely customizable, this rifle can also be a personal defense firearm at less than 36 inches long, to a sniper rifle over 50 inches.

Standard magazine (or clip, if you prefer) is 30 rounds, but aftermarket 5, 10, 20, 30, 40, 60, 90, and 100 round magazines are available as well, but only the 5 round, non-detachable clip is legal in California. These clips are breech loaded, and do NOT come off. The reason for this is because of the Assault Weapon Ban that The Clinton Administration put into affect, and this method of semi-automatic action slows the loading process and is supposed to reduce murders. All it did was boost illegal weapon sales.

With the modular accessory rail, hundreds of different aftermarket accessories are available. These range from simple, and relatively cheap in price, tac-lights, vertical secondary pistol grips,to night-sights, to bipods, to thermal scopes, to night-vision scopes and infrared scopes beyond normal mag-scopes with somewhere around 20+ compatible scopes. Other accessories are different stocks, from collapsibles to solid body, to skeleton, to adjustables.

These rifles, when sighted in are accurate up to 500 yards, with a range well beyond that.

The semi-automatic feed uses a direct gas impingement system. (If lost with this term, use wiki)

This rifle was designed by Eugene Stoner in 1958 as an updated, lighter version of the AR-10. The design was initially submitted as a new rifle for the US Armed Forces, and is what the M-16 was based off of.

Overall, this is a very effective weapon for home defense, hunting, sharpshooting, and just fun at the range.
Possible calibers for the AR-15 are:

.223REM
5.56x45mm NATO
(Yes, the NATO round is different from a .223REM. The NATO round has higher power, and needs mods to the weapon to be fired safely. Commonly confused and called the same as .223REM, because they have the same physical dimensions but different power levels)
.22LR
6.5 Grendel
6.8SPC
.45 Bushmaster
.300 Whisper
.458SOCOM
9mm Parabellum
7.62x39mm
.50AE
.50 Beowulf
.50BMG
(All these .50s are different power ratings and dimensions, but the bullet itself is the same size.)
.45ACP
by Brian Keeney November 13, 2006
 
7.
An assault rifle manufactured by Colt. Used by Military worldwide because of its high fire rate and accuracy. Designated by the U.S. Military as the M-16.
When the S.W.A.T. team pulled their AR-15s the criminals surrendered the hostages and gave themselves up.
by J.Rambo August 19, 2011