The JMAC 360HD KeyMicro Muzzle Brake in 5/8×24 shoulder mount (JMAC part no. 360HD-30S-KM) is a recoil reduction device that combines JMAC’s graduated port design with a KeyMicro suppressor mount. This 5/8×24 version is a shoulder mount made for AR-10 hosts. It is made from 17-4 PH stainless steel with three sacrificial baffles that take the first blast of gas, so the suppressor behind it wears more slowly. JMAC lists the 360HD as needing no timing and having no barrel length restriction, which makes it a fit for short-barreled and high-pressure builds.

Key Specifications

• Thread size is 5/8-24 shoulder mount, made for AR-10 hosts with 5/8-24 threads.
• Weight is 2.85 ounces, a figure worth knowing when you balance a suppressed rifle.
• Construction is 17-4 PH stainless steel, chosen for hard use at the muzzle.
• The finish is QPQ black nitride, which adds corrosion and erosion resistance.
• No timing is required and there is no barrel length restriction, per JMAC.

Frequently Asked Questions

What does the 5/8×24 JMAC 360HD KeyMicro fit? JMAC lists this version as an AR-10 shoulder-mount application with 5/8-24 threads, accepting any KeyMo or KeyMicro equipped suppressor or accessory.

Does the JMAC 360HD need to be timed? No. JMAC lists the 360HD as not requiring timing, and it has no barrel length restriction. JMAC recommends professional installation, 30 to 40 ft-lbs of torque and Rocksett on the threads.

Buy the JMAC 360HD KeyMicro Muzzle Brake, 5/8×24

Pair it with a KeyMo or KeyMicro equipped suppressor, or run it unsuppressed as a muzzle brake. Order it through AR muzzle devices and it ships fast from our Lubbock, Texas gun shop.