I have wanted an AR for some time now and I finally have some money to do it. I want to put together an AR that is very durable, the glock of ARs if you will. Is there a good place to find out which parts are built for more abuse and harsh conditions? I am starting to compile information and would love some tips and advice! As of now I am leaning toward the simplistic route and buying the colt 6920 and making a few minor changes or buying the pieces individually. Everything I have read has pointed me in the colt direction for a good price point and reliability.

I would think the Colt would be pretty tough as-is.

Buy it, shoot the shit out of it, and then figure out what you really need.

Since nearly every firearm I've ever purchased I've changed it in some way or another, I've come to realize that I should just START with the parts I want and go from there.
Do some research and then buy your upper and lower, then buy what you want/need to finish it.

Yeah, What he said! Colt is a tough azz gun as is. Anything after that is cosmetic upgrades.You just can't really go wrong with a Colt 6920. Oh and Welcome aboard

My sentiments exactly. To many guys are asking what AR or parts they should buy. Do the research like some of us do and make an educated decision. I do not ask anyone about what I should buy. If someone happens to mention something I have never heard of, I Google it and do my research on it. Doing searches is the best way to find things. Also, read through some of the specs guys list about their builds and you can get a good idea of what is being used. I will say this, BCM is a good one-stop shopping place. They do not stock junk. Palmetto State Armory, Primary Arms, Midwest Industries, and Del-Ton are but a few of the places to visit.

For that kind of durability and reliability you need a rifle not a carbine.

*Edit to add*

By Glock of AR's I take it to mean goes bang every time, anvil tough and seems to last forever with minimal maintenance.?

The AR15 and the 5.56 round were co developed together as a system. That system was originally a rifle.  
AR15 type rifles operate at standard port pressures and gas volumes and chamber residual gas pressures to give standard extraction values.
The BCG's operate at standard reciprocation speeds giving proper time for magazines to present rounds for feeding. The parts are subject to the standard levels of stress they were designed to handle.

The carbine variants are a departure from that system and it's operational physics and engineering.  
Carbines operate at elevated  port and chamber pressures. The increased BCG reciprocation speeds and earlier than rifle bolt unlocking places additional torsional stress on the bolt body and higher loads on the locking lugs at the time of unlock.

Innumerable pages have been posted on these subjects here and elsewhere.
Broken bolt, failure to extract, gold spring, feed ramps, extractor spring buffer are some things worth researching.  Google is your friend.

If the end goal is Glock like reliability in an AR15 type, the rifle will get you closest.
If the end goal is Glock like durability in an AR15 type, the rifle will get you closest.


Many opinions (and possibly some derogatorys) will follow this post but above are true and verifiable facts.

The 5.56 chambered chrome lined chamber and bore barrel and the M16 bolt carrier group were, and still are the military standard. These are the core of the firearm. Buy these two parts and the  lower parts from a reputable company and the gun should be durable and reliable. In the current market place this firearm can be completed for less than $600.

I will completely agree with the post although add, that there are some rather large detractors to a rifle length gas system.  Length and weight being the primary ones.  (I also say this owning a 20" barreled AR)

It really all boils down to what you want to do with the rifle.  Is this going to be something you will take to the range and possibly use in a proverbial "SHTF" scenario?  If so, a 20" rifle gas AR may be the choice for you.

Is this something you will use in a few classes as well as HD/SD?  Well I'd say something with a shorter barrel is in order.

The military transition to the issuance of primarily 14.5" AR style weapons has really helped the development of some well thought out advancements that make the M4 damn near as reliable as the original 20" M16A1.

If a shorter style AR is what you're looking for the Colt 6920 really fits the bill and adding accessories as you like should work for you.