Want this question answered?
222, 223 and 9mm
If it is one of the recent Colt .22LR AR15 rifles, then the answer is no - they are completely different internally.
Colt has not offered a AR15 in 308
AR15, M16, M4, Ruger Mini 14
36
50-1200 usd
$800.00
401 - 178 = 223
5.62 is bigger
Shank (.223 Remington) - 0.4370 / (NATO 5.56) - 0.4370 / (Difference) - 0.0000 Base Diameter (.223 Remington) - 0.3760 / (NATO 5.56) - 0.3780 / (Difference) - 0.0020 Shoulder Diameter (.223 Remington) - 0.3553 / (NATO 5.56) - 0.3560 / (Difference) - 0.0007 Neck-2 (.223 Remington) - 0.2550 / (NATO 5.56) - 0.2550 / (Difference) - 0.0000 Neck-2/Case Mouth (.223 Remington) - 0.2540 / (NATO 5.56) - 0.2550 / (Difference) - 0.0010 Freebore Diameter (.223 Remington) - 0.2245 / (NATO 5.56) - 0.2270 / (Difference) - 0.0025 Pilot Diameter (.223 Remington) - 0.2180 / (NATO 5.56) - 0.2180 / (Difference) - 0.0000 Base-to-Case Mouth (.223 Remington) - 1.7720 / (NATO 5.56) - 1.7750 / (Difference) - 0.0030 Base-to-Shoulder (.223 Remington) - 1.2340 / (NATO 5.56) - 1.2380 / (Difference) - 0.0040 Neck Length (.223 Remington) - 0.2200 / (NATO 5.56) - 0.2180 / (Difference) - -0.0020 Freebore Length (.223 Remington) - 0.0250 / (NATO 5.56) - 0.0500 / (Difference) - 0.0250 Rim/Belt Thickness (.223 Remington) - 0.2000 / (NATO 5.56) - 0.2000 / (Difference) - 0.0000 Shoulder Angle (Degrees) (.223 Remington) - 23.0 / (NATO 5.56) - 23.0 / (Difference) - 0.0 Throat Angle (Degrees) (.223 Remington) - 3.1 / (NATO 5.56) - 2.5 / (Difference) - -0.6
Try looking at this, it may give an idea. http://biggerhammer.net/ar15/ar15serial.html Mike aka nfmMike @ ar15.com forums
The AR15 is a 5.56x45 rifle. Incidentally, it is also capable of chambering and firing the .223 Remington, which is similar in dimension, but the two are not identical. That's the norm. AR15 rifles can be had in a number of calibres nowadays, to include 6.8x43 Remington SPC, 6.5 Grendel, .458 SOCOM, .50 Beowulf, 5.45x39, 7.62x39, .204 Ruger, 9x19 Parabellum, .40 S&W, .45 ACP, 6x45, .450 Bushmaster, and others.