No one, besides the odd Olympic (and I don't think they even do it anymore), makes cast receivers. The flashing you see is from the forging of the lower and just hasn't been milled off. See here for more info:
http://ar15.com/forums/topic.html?b=3&f=12&t=318113All lowers these days are pretty much equal in terms of function. It pretty much comes down to what rollmark you like the best and how much you are willing to pay for a name. High Standard, Double Star, and Stag are cheap, whereas Bushmaster and a few others are $60-80 more. And some of them are made by the same company before they are branded by the rollmark. As said, refer to the link. Finish might be a little different, but they should all fit pretty well. It's when we start refering to complete rifles that Armalite=Busmaster=Colt=RRA>>>>>>>DPMS & Olympic comes in to play. Pretty much everything from the ABCR manufacturers carries a pretty decent warranty, are well made with quality parts, and tend to work all the time. It's some of the lower end, budget manufacturers, such as DPMS and Olympic, where issues pop up, and everything isn't always up to par. One persons' runs great, while someone elses won't run at all. And the customer service isn't always the best with them either.
That being said, I suggest to never buy a complete rifle. Buy a stripped lower and build it how you want. The buy the complete upper of your choice. Why? Because when you buy a complete rifle, that costs, say $800, you've got to pay the excise tax on the whole rifle. When you buy a $110 stripped lower, you only pay the tax on it. And then you can build it up how you want, while not having to settle for something off the shelf, then spending more money "fixing" it to the point where you like it. Plus, the only thing you need to buy from a dealer is the lower; everything else can be ordered and shipped directly to you.
As far as accuracy, the barrel you use and the trigger are the two major things that contribute to accuracy. But don't expect to have the best of both of those and shoot MOA groups at 600 yards without optics unless you are a highpower competition shooter. I'd go with a quality chromelined barrel and put at RRA two-stage trigger in. If you're wanting to building a preceision rifle, White Oak Armament (WOA) makes great SS barrels, and the RRA trigger will do you well, but there are a plethora of target triggers out there. But be prepared to drop some cash on optics and good rings. No sense in having a WOA SPR barrel and Geissele DMR trigger if you're going to be using open sights.
That's my $0.02. Building is pretty easy. Even the upper.
[This message has been edited by Log (edited 4/24/2008 11:03p).]
