This topic is addressed about twice every week. You would find the answer to your question if you cared to use the search function. Now to answer your question.
There are three groups of ARs: military spec, consumer spec, and precision built spec. Military spec is a AR built to the same quality, and spec as military rifles. That means 1/7 twist crome lined barrels, F marked front sights, M16 bolts basically the rifle is the same as a military issue except the burst fire capability. Colt, Noveske and LMT, are the only companies that sell such rifles. Of course you will pay for those features. Below them are companies like Sabre, S&W, and CMMG that come close to military spec but use some consumer rifle part. A step below that is consumer rifles that use few if any military spec parts: Stag, Bushmaster, RRA, Armalite, DPMS, Olympic in addition to several other companies round out this list. Consumer is what most of us are, and we will likely see the difference between a consumer and military spec rifle. If you will be shooting thousands of rounds a year then you might want to look at a military spec rifle, otherwise don't waste you money. All these companies produce similar products. Just look for the one with the features you want at the best price. Precision built rifles come from companies such as JP enterprises, Wilson Combat, Les Bauer. My choice is buy a separate lower then a kit from a company such as CMMG. You will get near military spec but at your price range.
