Just when you think the AR 15 world has reached its peak someone comes along with something seriously interesting. The Garrow Arms Roller locked AR upper proves that. This upper is chambered in 17 HMR and is designed to fit and function with any standard AR lower with a mil-spec trigger. Installation requires a proprietary buffer spring and buffer block that comes with the upper. Other than that its a drop in system. It comes with a specially modified magazine that fits in a standard 5.56 magwell without modification.
Why a Roller Locked AR?
Why would you need a roller locked AR? I mean they’ve been working perfectly fine for generations without the need for a roller locking system. The roller locked design is a same and efficient method of producing a gas operated 17 HMR semi-automatic rifle. Semi-auto 17 HMRs exist but rely on a blowback system. Combining rimfires and blowback can create a potentially dangerous situation. Out of battery detonations happen, and a blowback system increases the risk of an out of battery detonation. That’s something you really don’t happen with a round like the 17 HMR.
A gas designed roller locked AR design ensures the bolt is locked into place before the rifle can fire.
A gas system is also going to be much more reliable. Slight tolerances in your standard centerfire round aren’t likely to be noticed. Whenever you start shrinking rounds and you get something as small as the 17 HMR those tolerance become a much bigger deal. A slight tolerance in a small round could mean it’s not powerful enough to operate a lesser system. The bolt in a blowback system, in particular, has to walk a fine line between being light enough to allow the weapon to cycle and heavy enough to prevent case separation.
Why an AR?
This is a pretty easy one. The AR 15 is already an outstanding platform. You have a massive amount of stocks, rails, sights, optics, and more available for the platform. Plus with the number of people who own ARs, it’s just a good business decision. A roller locked AR may not be for everyone. Personally, I really appreciate the design and I’m glad people are still looking forward with the AR design. Stand by for the full review, coming very soon.
