Colt introduced the R6830 Sporter Lightweight 7.62x39 in 1993. They were offered until about 1995-1996.
The gun itself had an A2 type lower receiver with the standard reinforcements, mag fence, large trigger/disconnector pins, sear block (only pinned on one side), and mil-spec size forward takedown pin (although they still came with the two piece screw and may or may not have come with the fence drilled to accept the spring and detente for a push pin). It had a standard A2 upper receiver, the elevation wheel for the rear sight has paint markings on it calibrated for the 7.62x39's ballistics, a 16" barrel, no bayo lug, and an A2 type flash suppressor (Obviously on the pre-bans only. I've been told that the flash suppressor is the same type used on the 9mm AR15s. The standard USGI flash suppressor doesn't have a large enough opening to accomodate the 7.62x39).
The only parts unique to the 7.62x39 AR15 are the bolt, extractor, and barrel.
True, SKSs and AKs may indeed have been/are cheaper as simple bullet hoses, but the 7.62x39 AR15 combines close range knock down power with a far higher degree of accuracy. I find it to be quite a fun combination.
Good higher capacity mags are the Achile's heel of this gun, but in my experience it really isn't that of a deal, certainly nothing insurmountable. Post-ban MWG 10 rounders have proven reliable, the pre-ban USA 20 and 30 round mags either work great or can usually easily be tweaked to, and the two Scherer 30 round mags I have work excellently. If you are buying one just to use for hunting, the Colt factory 5 round mags function excellently or you can take just about any USGI mag in decent condition and expect it work reliably with 6 or 7 rounds of 7.62x39.
Here is my Colt R6830. It has become one of my favorite ARs. My collection will never be without one again.
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