"Will it hurt my ears when I'm hunting?" That's a common question from hunters who are interested in putting a muzzle brake on their rifles. The Brockman Brake let's you open and close the gas ports. You can open the ports and enjoy the recoil reduction while working up loads, sighting in, and practicing. Then, just close the ports if you want to go hunting with normal muzzle noise. Same accuracy.The Brockman Brake was pendulum tested to reduce recoil by up to 47%. You'll shoot better and have more fun with less recoil... Off the bench or off-hand.Physical Requirements - We install Brockman Brakes on calibers from .223 to .338 with minimum muzzle diameter of .730" and maximum muzzle diameter of .875". The brake itself is .875" and bevel the rear to transition nicely with your barrel diameter. This price includes our Precision Installation process.See all of our muzzle brakes and a description of our installation process on our Muzzle Brake Home PagePlease allow approximately 6-8 weeks for installation.