You will have to call Colt and tell them the serial number.
Variant of the AR-15 manufactured by Colt. It had a 'slab side' lower and no forward assist.
Colt has not offered a AR15 in 308
If it is one of the recent Colt .22LR AR15 rifles, then the answer is no - they are completely different internally.
According to info available on ar15.com, your weapon was manufactured in either late 1972 or early 1973. I own one made in 1974.
Call Colt and they will tell you.
Proofhouse.com. Call Colt also.
@ 40 inches.
The AR15 series
Proofhouse.com has Colt sn data.
You will have to call Colt and provide the serial number to find out.
What is the manufacture date of a Colt AR15 rifle serial number 192754 model SP1
Try AR15.com Try AR15.com