Help with barrel ID

I recently bought a pre-ban (we still have an AWB in MA) Colt AR. The lower is marked “SPORTER MATCH HBAR”. The upper is an A2 style with a 16" heavy barrel. The upper receiver, bolt, and carrier have Colt markings. However, the barrel has no markings at all. My research seems to indicate that Colt only made complete HBAR rifles with 20" barrels. Could this be a factory barrel? If so, would it be 1/7 twist? Any help would be appreciated.

Jim

xxxxx

Nothing anywhere on it.

In my experience I don’t believe that to be a Colt barrel.

Looks like a bottom-feeder barrel. The roll pins are a dead giveaway.

Thanks guys. I didn’t think it was a Colt. I’m anxiously awaiting the new LMT M4 upper I ordered for it.

Handguard cap is not Colt either.

Lack of markings, roll pins & marks on the FSB: barrel probably swapped.