Originally Posted by UNKNOWN_370

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Get advice from guys that have actually shot a weapon and can judge them appropriately. Go through forums and you tube. See what are the pro's and cons. We can tell you brand X and Y is this and that. But often, Ar advice will be biased. Keep it moving on the reading. Dont just look at Core- look at the tried and true brands, supposed crappy brands. find both positive and negative reviews. Weigh the reasons out and make sure the negative or positive sound valid enough to take the recommendation. "Things like it just looks so cool is not a good review." Endurance test vids are a good indicator of performance...
At first, the more you read, the more you will get confused cuz rule of law and brand loyalty shouldn't go together, but it does. Over time, the truth is revealed and you find out what really works and what doesn't. I'm not saying you're not going to get generally good advice, but a lot of advice comes from limited research. One may know something the other doesn't.

Lastly, get out to ranges. Test em out for yourself. Shoot your friends AR's. That will add to the reviews. You can usually get a feel for popular brands at ranges. (Colt, bushmaster, Stag, RRA, etc)
AR's are a big world with too much info. but once you have as much knowledge as possible? It makes life easier. Lastly, off the rack, there's no such thing as the perfect AR. That's why they have such a huge aftermarket.

GL and happy shooting.