You are going to get a lot of different answers on this one. I personally would say that most of the major brand names will be ~ equal. I have a DPMS, but I doubt it is any better or worse than a Bushmaster, Colt, Stag, Rock River, etc. There are some high dollar AR's out there that may be of a little higher quality, but I don't really think they are worth double the money. Your call. I am happy with my DPMS - it has never given me cause to doubt it.
There are many opinions about this, and mine is just one other...but I'll post based on my experience, education about the rifle, and training. Your mileage may--and probably will--vary.
There are a number of things that you should look for when selecting an AR15, whether it's a rifle, carbine, SBR, or any other configuration.
First, look at the construction of the rifle. Are the parts well finished and well machined, with no rough spots or edges? This applies to the parts as well.
A telltale part to look at are the handguards. Some companies manufacture flimsy parts that are meant to cut costs. Take a close, hard look at them.
Next, look at the quality control. Are the parts in spec? Take a caliper, measure the holes in the lower from center to the top of the receiver--on BOTH sides. Are the measurements the same, or are they skewed a bit? This means that your parts will not align properly.
Look at the internals. Do you see the dreaded mold lines of the MIM part--or the solid surface of forging and machining?
For the M4, it is vital that the feed ramp is cut properly. Just slapping a short upper on a bottom does NOT give you an M4--or even a good carbine.
Now, look at the bolt carrier group. Is that carrier key staked on properly? The metal around the carrier key screws should be swaged inward, evenly, actually touching the screw and contacting it enough to impede movement. Is the metal swaged--or struck with a mechanical hammer (sharp indents)? Small things like the firing pin retainer tell a story, too. Are the ends radiused for easy insertion, or do you have to go through the tortures of the condemned to get it back in? And, no--it is NOT just a cotter pin.
How about that buffer? Is it filled with lead shot, or are there actually buffer weights inside? Moreover, do you have the CORRECT buffer and spring for the rifle/carbine?
How about chrome lining? Trust me, the AR has chrome lining in it for a reason. Some folks will say "oh, the chrome is in the steel", and refer to chrome-moly barrel steel. Yes, it has chromium in it--but it is NOT chrome lining. Unless you are building a match upper, you NEED chrome lining in that bore, AND in the chamber.
Finally, look for those magic letters, "C MP". This means that the rifle's parts were magnafluxed after manufacture.
So, who fits the bill?
To be sure, Armalite puts out a good weapon. So does Bushmaster. Stag Arms is IMHO the best rifle for someone on a budget--you can have a really nice rifle, assembled to your specs for a good price.
But, when all is said and done, there is only one AR out there that has all of the above; only one that is spec'd out for the US Military, with the proper CAGE codes and NSN's. The only one that is serving with our troops of all branches overseas, right now--and will be serving for some time to come.
I bought one--yep, it was more expensive than most fully tricked out versions. But reliability was more important to me than cost; and, since I use the rifle for serious social (or antisocial) purposes, I wanted something that I could bet my life on--and I do.
You see it in my avatar--it is a Colt LE 6920. Make the barrel 2" shorter, and put in a full auto fire control group, and you would have the M4A1. The three round burst group gives you the M4.
When all is said and done, consider that if it's not a Colt, it is--literally--just a copy. Only Colt has the copyright and patents to use the name, AR15.
My rifle cost me $1300.00, out of the box--and it was money well spent.
(Did I mention that I just love that prancing pony, too?)
RRA, Stag, Double Star, you can't really go wrong. When you start talking about Bushmaster and Colt, your really paying extra simply for the name. Something else to keep in mind, unless you live in a jungle, or plan on shooting your rifle and letting it sit for a year, a chrome lined barrel really isn't going to do anything for you.
I loved my Stag, may she R.I.P. Lost it in a house fire, and I plan on replacing it with another Stag. There's a lot of good ones out there though, haven't found too many that I don't like! DPMS, Bushmaster, Colt...they're all good. It's a matter of how much you want to pay extra just to have a certain logo branded on it, in my opinion.
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When they come for my guns, I'll give 'em the bullets first!
CMT and LMT parts are THE choice of the Military Bone Yards - when an M16/M4 gets a barrel shot out, or some other problem arises - they turn to CMT and LMT. Go Lewis Machine and Tool, Stag, or CMMG if you want Military Grade. Go Les Baer ($2000 and up...) if you want the best there is.
CMT is CMMG and Stag
LMT is LMT (Lewis)
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When you argue with forum trolls, they win.
I just bought a Rock River Arms. I feel it is the best AR for the money right now. The 2 stage Match trigger is wonderful. They have good customer service and a great reputation.
I have heard.....yes I have no person knowlege. That Colts customer service isn't the greatest and that Civilian sales are secondary in their company. Military contracts and LE sales are a higher priority. Colt may have the copyright and patents but unless I am mistaken colt bought them from Armite. After all that is where the AR part of AR-15 came from.
Now don't get me wrong. Colt makes a good rifle. So do many other manufacuturers. Find something you like in your price range and you will be just fine!
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"I don't go shooting without my guns and they don't go shooting without me!"
I've been very satisfied with my Bushmaster M forgery. I've changed a few parts and cleaned up the trigger. Everything fits nice and tight, I would buy another.
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Married men live longer than single men do, but married men are a lot more willing to die.
IMO.. the best one out there is the one that fits your budget and your style.. By style, I mean, the one that you like.. I personally have built both of mine from scratch using everything from DPMS to Knights Armament.. I like building them, for one reason.. it's to my specs the first time around and I don't waste any money on replacing parts because I didn't like the front sight or something silly like that..
With that said, you do have to look at the quality of the parts you buy.. I wouldn't recommend ordering something from a catalog or internet for the fact, you don't see the part first hand and you might get something in the mail you didn't expect...
As far as quality and reliability, if you're not shooting competition or going to the desert or jungles, most companies will suffice..
My new M4 
