I picked up my new rifle from 2A Sales on Friday, (thanks guys) and I took it for a test drive today. I thought I'd post some of my thoughts.
Quality: First off I have to say that I'm generally not a huge fan of Ruger. I have nothing against them but I wouldn't place them in a the same category as some of the other high end firearms. I have owned a few Rugers and in my experience the production quality seemed to be hit or miss. However I have to say I was totally impressed with the SR-556. The build quality is outstanding, it's as solid as a rock. There is absolutely no play between the upper and lower receiver. Normally there is a little play even after a receiver wedge is installed but the SR-556 was so solid that it felt like the upper and lower receiver was one solid piece. This thing is a tank.
Finish: The finish is above average, I would say it is comparable to a Bushmaster or RRA. The finish is consistent across the upper and lower receiver and matches the hand guards and accessories very well.
Stock: There was a slight wiggle in the factory M4 stock, which is normal but it has always bothered me so it was removed and replaced with a Magpul UBR.
Grip: The factory Hogue grip was very impressive, probably one of the best factory grips I've ever handled. However I personally like the look and feel of the Magpul MIAD (plus it matched my stock), so the Hogue grip was replaced.
Flash hider: The Ruger factory flash hider was also replaced with a standard A2 because I've been told that it has a tendency to kick up dust while in the prone position....plus I thought it looked like ass.
Bolt and Barrel: The bolt is chrome plated and the barrel is chrome lined, which made cleaning a breeze. I also have to add that one of the sand bags I was resting on broke and some of the sand got inside the upper receiver but the rifle never missed a beat. I'm not sure if that was due to the chrome plating or the gas piston system but I thought it was worth mentioning.
Gas Piston: The gas regulator has 4 settings that range from totally off (0) to all the way open (3). I ran the first mag on setting (1) and had three FTF / FTE. After that I moved the gas regulator to position 2 and put 200 rounds down range with no other issues. Some people have noted that the barrel and gas block seemed to run hotter than normal but I didn't really find it to be any worse than my DI AR. As for the dreaded carrier tilt that everyone is complaining about, I think it's much to do about nothing. I checked the rifle multiple times during the course of the day and I did notice that some of the finish was starting to wear in the first half inch of the buffer tube but it seemed to only wear to a point and then stopped getting any worse. Maybe I'll change my tune later but I really don't see the big deal. Cleaning the Gas system was also easy because of the simplicity of the design but the gas piston does get very dirty.
Trigger: There is no other way to put it, the trigger is atrocious. It came from the factory set at 9 pounds. Come on Ruger, really, 9 pounds? The trigger breaks clean and has no play but at 9 pounds it takes some getting used to. I'm hoping that it will loosen up a bit after break in, if not, it's getting replaced as well.
Controls: The controls are tight, no issues there.
Weight: The damn thing is heavy. 9.5 Pounds with the UBR , Eotech and an Empty mag. That's a little over a pound more than my equivalent DI rig. I also have to note that the SR-556 is a little front heavy with the factory stock, but with the UBR it's nicely balanced......but heavy none the less.
Accuracy: Considering the trigger weight I was thoroughly impressed with the rifles accuracy. I was able to bust clays at 50 and 100 yards with no problem and I was able to smack steal at 300 fairly consistently. Is it a sniper rifle capable of shooting golf balls at 500 yards, no but I would put it in the 2 MOA range with standard ammo.
Recoil: The Recoil was slightly less than a DI gun but that could be because of the additional weight.
Overview: In my opinion the SR-556 is one of the most well equipped "factory" rifles available today. I upgraded some of the parts because of personal preference but you could certainly buy a SR-556, slap some optics on it and be done without a second thought. Overall I was impressed. It is just a fun gun to shoot. The rifle does have some minor flaws like the trigger and overall weight but nothing that would prevent me from recommending it to a friend. A lot of people questioned Ruger for entering the AR market so late in the game but as far as I can tell they got it right.
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Looking for a job as the 2 A Sales minister of propaganda? Pay sucks but has great benefits. 
