I've often heard and read that lightweight barrels on AR-15's weren't as consistent as their heavier counterparts when it comes to accuracy especially after they heated up. I recently purchased one of Rainier Arms RUC rifles with a 16" lightweight barrel. I called Rainier prior to placing my order and they told me that Daniel Defense manufactured the barrels on that particular gun. I used to own a complete Daniel Defense gun and was pleased with it. I own several AR's, but this rifle had many features that were a first for me. The rifle is my first mid-length, first with anything other than an A2 flash hider, and my first with a light weight barrel.

When I received the rifle I was thoroughly impressed by the weight and handiness of the rifle. After I shot it I was even more impressed. I feel like I've been missing out on my other rifles with gov.'t and heavier profiles. I showed the rifle to several of my co-workers, they were impressed with the fit and finish and overall feel of the rifle, but some had their doubts as to the lightweight barrel. The video below was mainly to satisfy my curiosity, but I thought a couple of other people might be interested as well so I filmed it. I knew setting out that I'm unfortunately not a good photographer, I found out I"m a worse videographer. Hopefully it conveys the point well enough.

For the "test" I ran 100 rounds through the rifle. I shot an initial 10 shot group at 50 yards to establish a baseline for the zero and then ran 80 rounds through the gun on a select fire lower. Immediately after shooting the 80 rounds I shot another 10 shot group at 50 yards on the same initial target to see if the group opened up and if there was a shift in zero. I figured 100 rounds was enough to heat the gun up sufficiently without being a colossal waste of ammo. All of the ammo was Federal Tactical 55 gr. soft point --223 not 556.

http://youtu.be/w9fmsilDEXo

The second 10 round group may have showed a very slight shift down, but overall I'm happy with how well it maintained its accuracy. I can't see a lightweight barrel being any detriment in any realistic scenarios.

I've only had time to run a few hundred rounds through the rifle, but based on its handling characteristics and consistency I see more lightweight barrels in my future.