Sure, it's possible, but ultimately pointless. The .22 LR is a much shorter projectile than a 5.56 or .223 projectile, and if you tried running such a cartridge through a 5.56 or .223 chamber, you wouldn't get proper headspacing from it. The end result would most likely be a catastrophic failure of the weapon which could injure or kill the firer or others.
If it is one of the recent Colt .22LR AR15 rifles, then the answer is no - they are completely different internally.
No.
No, but American Firearms and Tromix have made upper receiver for AR15 rifles and carbines chambered in .50 Action Express.
That's a smoking deal on the Mosin-Nagant. That's the one I'd go with.
The typical AR15 fires the same type of bullet as the M16: a .223 caliber (5.56mmx45mm NATO) round. There are AR-15 rifles that have special barrels made for a variety of popular cartridges, even the little .22LR.
An AR-15 is a rifle that uses 5.56 mm bullets. It is a semi-automatic rifle. This specific type of bullet is the most commonly used bullet amongst the NATO forces.
Try AR15.com Try AR15.com
The US Army presently uses the M4 carbine, a shorter and much modified version of the Armalite AR15.
Colt has not offered a AR15 in 308
1959
Yes
By it's serial number. Go to www.proofhouse.com and under 'long rifles' listing look for AR15 Sporter