In the Line of Duty: The FBI Murders
 

http://www.imfdb.org/images/3/3c/ITLD-AR15-2.jpg

I think the rifle ain't a Colt AR15 sporter. More like an M16A2. The shape and rear sight of the carrying handle/rear sight is a dead giveaway.

Colt AR-15 was what user "Markit" labeled it as. I got all his smaller images replaced and a lot of new ones added. I'm also trying to read up on the actual shootout and put in the page.

You do know civilian-legal semi-auto versions of the M16A2 do exist, don't you? ;)

Yeah there are several Colt Sporters that are built like A2s, as well as a dozen other A2 designs built by other companies. Could be any one of them.

Here is a close up of the receiver. Maybe it'll help.

I don't think the A2 version was called a "Sporter". The AR-15 that looked like an early M16 was called the Sporter 1 (SP1), and the M16A1 look-a-like (with forward assist) was called the Sporter II. But I thought the M16A2 look-a-like was just called the AR-15 A2 (or the AR-15 Government Model HBAR for the version with the Match barrel).

That's what my Gun Digests from the 80s say, at least...

Definitely an A2-style receiver. The question is whether it gets fired on auto or not. And even if it fired on auto, that means it's one of the Hollywood "Franken-M16s" (an A2 upper on an A1 lower, or some other full-auto lower).

I only rented the movie and had to return it. That rifle was only used in that scene. Both Platt (Soul) and Matix (Gross) seemed to fire in burst during that scene in the woods.

There was a run of A2 rifles called Sporter HBARs, but you are right about the Sporter I and II.The AR-15 A2s that I've seen were with 715 uppers, but I think I came across one with the A2 upper once too.

Gun Digest 1990 says that the 715/C7 look-a-like model was called the "AR-15 A2 Sporter II". It's basically a budget version of the A2 model - by subtracting the A2-style rear sight, it was sold for $70 less than the regular A2 model, and $120 less than the HBAR. There were also corresponding Carbine models.

Also, the other models are called, "AR-15 A2 Government Model" (the M16A2 look-a-alike) and "AR-15 A2 Government Model HBAR" (same gun with the match-grade barrel).

I'm not too sure Matix was firing in bursts, because it seemed to me (although the scene only shows part of his hand) that he was simply pulling the trigger quickly.

If I had to guess, I'd say it's most likely a civilian AR-15 A2. Depends on the lower receiver (if it lacks the fencing around the mag release, that would be consistent with the AR-15 A2s in production in the mid- to late-80s).

I think this might also be the earliest movie to feature A2-style guns.