You will have to call COLT
The Colt AR-15 Sporter II with Serial Number SP326210 was manufactured in 1992. Colt's serial number lookup can provide specific manufacturing dates, but generally, the Sporter II models were produced predominantly in the late 1980s to early 1990s. For precise verification, consulting Colt's customer service or reference guides on their serial numbers can offer confirmation.
You will have to call Colt to find out.
Colt data at Proofhouse.com
You will have to call Colt with the sn to find out.
You will have to call Colt to find out
AR-15 is a trademark owned by Colt - thus, no other manufacturer may market their rifles as AR-15 unless they are specifically licenced from Colt to do such. LAR-15 is simply Rock River's alternative name to "AR-15" in order to avoid infringing on Colt's trademark.
The Colt AR-15 rifle with Serial Number 100677 was manufactured in 1962. Colt's production of the AR-15 began in the early 1960s, and serial numbers from that period can be referenced to determine their manufacturing dates. For precise information, it’s best to consult Colt's official records or a reliable Colt AR-15 serial number database.
Proofhouse.com has Colt sn tables. You can also call Colt and they will tell you.
Colt has not offered a AR15 in 308
You will have to call Colt
you will have to call Colt to find out.