The Rock River Arms Entry Tactical AR-15, or more precisely the RRA LAR-15 Entry Tactical, is an AR-15 pattern rifle.  My particular rifle has a 16″ barrel with a 1:7 twist.  I wanted an AR-15 for a while, and after looking around I decided on the RRA.

The AR-15 design was created by Eugene Stoner when he worked for Armalite (hence the “AR”).  Armalite sold the AR-15 rights to Colt about 50 years ago, and nowadays AR-15 pattern rifles are manufactured by quite a few companies, including Rock River Arms (although Colt still holds the “AR-15″ trademark.)

The AR-15 is a gas operated, semi-automatic rifle chambered for .223and/or 5.56mm., and its design was groundbreaking when created by Eugene Stoner.  The use of composites to reduce weight while maintaining strength, and the use of a relatively small caliber round both stand out.  Similarly, the positioning of the stock level and in a straight line with the barrel, so as to reduce muzzle flip, also show Stoner’s skill as a firearms designer.  Perhaps most notable about the AR-15 is its direct  gas impingement system, whereby some of the gases produced by the burning gun powder are diverted through a tube beneath the front sight and sent directly against the bolt carrier.  This design does away with the need for a gas piston, as used in many other gas operated firearms, reducing complexity and felt recoil.  This system also means that the “dirty” gas is sent back into the receiver.  However with proper cleaning, this really isn’t a reliability concern.

AR-15 vs. M4 Carbine

As I mentioned above, the AR-15 is a semi-automatic firearm.  This means that it fires one round for each pull of the trigger.  The M4, the main battle rifle for American armed forces, is quite similar in design to the AR-15, with one critical and ever so important difference: The M4 is a fully automatic weapon.  It can fire more than one round with each pull of the trigger.  In other words, while the AR-15 and M4 look quite similar, they are worlds apart because the AR-15 is functionally no different than any other semi-automatic rifle.

Mechanically speaking, the M4 and AR-15 have different triggers, disconnectors, selectors, bolt carriers,  and hammers, so despite persistent urban legends, it is not all that easy to take an AR-15 and convert it into an M4.

Supported Calibers

The AR-15 is chambered for .223 and/or 5.56mm.  Most AR-15 can handle both .223 and 5.56mm, but some are able to safely handle only .223 (although I’ve never personally seen such an AR-15).  There are also conversion kits available to transform an AR-15 so that it can fire a wide range of calibers, ranging from .22 long rifle, to 9mm and up to .50 Beowulf.  The AR-15 is an incredibly versatile platform.  If I could only have one rifle, it would be an AR-15.


Eugene Stoner’s brilliance as a small arms designer can really be seen in the AR-15’s ergonomics.  Out of all the firearms I’ve held, I’ve found none to be more comfortable to hold than the AR-15 .  The pistol grip and the hand guard are perfectly placed.  The stock, which is in a straight line with the barrel, is also perfectly placed, helping to reduce muzzle flip when firing.  The controls are well placed too.   The light weight of the AR-15 makes it easy to hold and carry.  On a related note, it is one of the more beautiful rifles I’ve ever seen, although to be fair I prefer black plastic over wood any day.

Build Quality and Rock River Arms as a Company

Rock River Arms is known as a one of the best manufacturers of AR-15 pattern rifles, with good reason.  The fit and finish on my AR-15 is superb, and the first time I took it to the range, the other 3 shooters took a break to come admire it.  I was debating buying a Bushmaster AR-15, but after handling the Rock River Arms model, my mind was made up.

I’m also pleased to say that Rock River Arms is a great company to deal with.  I called them to inquire about different stocks and to get answers to a couple of technical questions, and they were quite helpful.  Even though they are cranking out AR-15s as fast as they can, given the gun buying boom caused by Obama’s election, they still had time to politely and correctly answer my questions over the phone.  Since they did such a good job manufacturing my rifle, I can’t personally speak about their servicing of rifles under warranty, but I suspect they are top notch in that regard too.


Rock River Arms promises 1 MOA at 100 yards, and I’m inclined to believe them.  I haven’t had as much time to shoot my AR-15 as I would have liked,  but I am looking forward to doing at lot more shooting in the coming weeks and months.  That said, accuracy is great.  Most people’s shooting skills are the limiting factor to this gun and not the gun itself.


Pretty much every accessory one could want or even imagine exists for the AR-15.  These include higher/lower capacity magazines, sighting options, tactical lights, different grips and handguards, different barrels, different flash suppressors, etc.  One could spend a lifetime (and a lifetime’s income!) customizing an AR-15.

Why I bought an AR-15

I was asked by someone why I bought an AR-15.  I have several reasons, each of which would have been enough to justify the cost in my mind.  Firstly, it is simply a nice rifle to own and shoot.  I enjoy firing it, and I correctly guessed that my wife would enjoy it.  Secondly, I was worried about Obama’s openly stated gun control plans, and how if they came to fruition, I might never be able to buy an AR-15 in the future.  Thirdly, given the possibility of future gun control laws that might ban manufacturing of the AR-15, and even the current run on AR-15s as people buy them out of fear of such possible gun control laws, it seems that the AR-15 is going to hold its value.  While I have no intentions of selling mine, it is good to know that it is a decent investment that is rather secure.  Finally, I recognized that while my shotguns and handguns might be effective at fending off a home invader or armed robber, their lower magazine capacity wouldn’t do me as much good during periods of prolonged civil unrest (e.g. the LA riots of the 1990’s, the Chicago riots of the 1960’s, the aftermath of Hurricane Katrina).  While I hope that I never face violent attack by a mob during civil unrest, and hope to never fire a gun at another human being, having the AR-15 and a few loaded magazines on hand is a rather cheap insurance policy.


If it isn’t obvious by now, I’m quite a fan of the AR-15.  And after holding and shooting many other manufacturers (CMMG, DPMS, Colt, Bushmaster), I am very pleased with the RRA AR-15.   It is a versatile rifle with a nice finish and a solid feel that is well designed and enjoyable to shoot.  I find the quality of the Rock River Arms AR15s to be exquisite.