More details please

[The Commander]

What I ment to say was:

AR Disigantion vs. Name

AR-15 ............ ??????
CAR-15 ........... ??????
AR-16 ............ ??????

And so on ....

[MrMurphy]

AR-15: The original name of the original rifle made by Armalite and designed by Eugene Stoner. Most of the original Vietnam-era Colt-made military rifles also had this stamped on them. It's the "generic name" now for this type of rifle.

The semiautomatic civilian-model Colt rifles also had the AR-15 model designation if I remember right.

The CAR-15 is the carbine model from the Vietnam era, in military service it was also known as the XM177. CAR stands for Colt Automatic Rifle, also said to stand for other things. Anywhere from a 10" to 14" barrel depending on what you had, and the collapsing stock fitted.

There is no AR-16 (there is the AR-10, which is the 7.62mm rifle the AR-15 descended from which looks similar).

The M16 is the military designation for the AR-15. The original M16 had no forward-assist to close the bolt and fired on semi and full automatic. It had the open-ended flash suppressor and the triangular forward handguard. The CAR-15 had a round handguard (like the new ones have).

The M16A1 was the improved model with a closed-end flash suppressor, the forward assist, etc. This was standard issue till 1983 or so.

The M16A2 (standard issue now) has a target-type rear sight (not necessarily a good thing) a slightly longer and heavier stock, round forward handgrips, a closed-bottom flash suppressor to not throw up dirt shooting prone, and has semi and 3-round burst (not liked much, it screws up the trigger pull), as well as a heavier barrel.

The M4 carbine has the collapsing stock, 14.5" barrel (some 10" and 11.5" are out there, but generally, 14.5"), a "stepped barrel" (heavy but thin in some spots to allow attachment of the M203 grenade launcher) and depending if you have an M4 or M4A1, has burst or automatic fire capability.

Most M4s are flat top recievers now for optics.

The M16A4 has been adopted by the Marine Corps, it is basically an A2 with a flattop reciever, and possibly a collapsing stock (have seen a few in pics, but most have the standard stock).