The US Army buys the M-16, not the AR-15. Replicas are not firearms and can't fire.
Try AR15.com Try AR15.com
Only if there was one made for an AR-15 upper, which there isn't.
If it is one of the recent Colt .22LR AR15 rifles, then the answer is no - they are completely different internally.
1959
Yes
Colt has not offered a AR15 in 308
By it's serial number. Go to www.proofhouse.com and under 'long rifles' listing look for AR15 Sporter
In October 1965 I used a M1 Grand in Basic at Lackland it was left over from the Korean war. All the new AR15's were going to Nam.
Depends on model.
@ 40 inches.
Its ar15