Great Lakes Tactical (GLT) is now selling a muzzle brake for .223 caliber rifles. GLT states the brake also acts as a flash suppressor.
The brakes are machined from 17-4 stainless steel and Melonite coated. I received a sample brake from GLT for T&E (range evaluation coming soon.) The machining and finishing all appear superb. I look forward to comparing this to the standard birdcage and other muzzle devices I have on hand.
The brake uses standard 1/2-28 threads and should work on any threaded barrel AR-15 on the market. The MSRP is $85.