AR 15 is the civilian version of the military's M4 carbine. Contrary to what most people believe AR doesn't stand for assault rifle, rather it stands for the original manufacturer Armalite Rifle. AR 15 is semiautomatic and does't meet Federal requirements to be classified as an assault rifle.
AR 15 is so legal in Kalifornia, now everyone is sporting it
by Nasor6221 July 01, 2015
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This gun SJWs claim is the spawn of all evil. Believe it or not, the AR actually is the Father of the M16, and the M16 was developed off it. It is now marketed as a Semi-Auto Rifle for civillians in America. Recently, there has been a Libtarded movement to ban it, following the recent school shootings.
Visitor: Oh, is that your M16?
Gun owner: No, it's an AR 15 man. Have you been playing too much COD recently?
by Nein_Definition July 14, 2018
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A scary black aussault rifle that shoots fully-semi automatically and is easy to obtain. A weapon of choice for shcool shooters, white supremest, and alt-righters
AR 15’s are responsible for 100,000 deaths each year
by A smol Hispanic child July 22, 2018
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a black plastic hunting rifle hated for being black and cool.
Johnny Spleenburger is the AR-15 champion! He can kill coyotes before he gets attacked by them
by CanukGuy May 21, 2020
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The gun that gets a real bad rep because it is used in almost every mass shooting. Although in reality it is used because it is very common and plentiful in America. The fake news media typically portrays the AR-15 as the "Most deadliest gun ever made" or that it is a "Weapon of War" although in actuality it is a civilian version of the M4A1 that is the REAL weapon of war.
The media acts as if the AR-15 is the only gun in existence.
by A Human Male July 21, 2018
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AR does NOT stand for Assault Rifle
50 Cent "Wanksta"

"what you know about AKs and AR-15s?"
by CubaGT February 12, 2007
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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
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