RE: Olympic arms AR-15s
I have two , O.A. AR's I built from there Parts ( matched upper & lower)and many more I built for customers , including some select fire M16's(lowers rec. were not O.A )and all were built with S/S heavy bbl's.( who needs chrome lined ). The only problem I have had and it was afterover twenty years , is a trigger sear partly sheared off on one of mine own and caused it to double tap once in a while. Mil. spec. triggers are really hard to work with to get a good trigger sear engagement , by working them you take off too much material and that reduces there workable life ( twenty years is pretty good ).
The new systems (match triggers ) were not available back then, like a lot of the upgrades available today.