Some imformation to consider before installing a muzzle brake
Quoted from the chuckhawks website
If the advantage of muzzle brakes is reduced recoil, the disadvantage is increased muzzle blast. As always, in the real world, there is no free lunch. The increase in muzzle blast with these devices can be literally deafening, even for shooters wearing hearing protection.
The muzzle blast from a powerful muzzle brake equipped rifle is so loud that even with hearing protection the shooter risks suffering some permanent hearing damage after a few shots. Earmuff type hearing protectors typically reduce noise by about 25 dB. A muzzle brake equipped magnum rifle (like a .300 or .338 Magnum) produces a sound pressure level (spl) in the 130-dB range, according to reports I have read. Thus the spl inside the hearing protector is in excess of 100 dB, a potentially damaging level.
For a hunter in the field, shooting without ear protection, the muzzle blast from a muzzle brake is immediately deafening. Nearly complete temporary deafness usually lasts from about a minute to several minutes after firing a powerful magnum rifle equipped with a muzzle brake. Later almost all of the shooter's hearing returns, but a certain amount is permanently lost, and the losses are cumulative.
From the link posted below
http://guns.connect.fi/rs/mounting.html
Muzzle brake effect: Reflex Suppressor is a highly efficient muzzle brake, due to abrupt reflection or blowback of muzzle blast in the first expansion chamber. The threading for a suppressor also serves for mounting a separate muzzle brake. Attention! The devices serving only as muzzle brakes are not recommended, as they increase essentially the shooter's noise level! The peak noise level to shooter may go up from abt. 157 dB to up to abt.167 dB with a .308 Win rifle if equipped with a muzzle brake. Such a noise level can cause permanent damage to unprotected hearing even with single shots!
From the link below
http://www.freehearingtest.com/hia_gunfirenoise.shtml
Table 2. CENTERFIRE RIFLE DATA
.223, 55GR. Commercial load 18 _" barrel
155.5dB
.243 in 22" barrel
155.9dB
.30-30 in 20" barrel
156.0dB
7mm Magnum in 20" barrel
157.5dB
.308 in 24" barrel
156.2dB
.30-06 in 24" barrel
158.5dB
.30-06 in 18 _" barrel
163.2dB
.375 — 18" barrel with muzzle brake
170 dB
Krammer adds that sound pressure levels for the various pistols and ammunition tested yielded an average mean of 157.5 dB, which is greater than those previously shown for shotgun and rifle noise levels. There was also a greater range, from 152.4dB to 164.5dB, representing 12 dB difference, or more than 10 time as much acoustic energy for the top end of the pistol spectrum. It should be noticed that this figure of 164.5 dB approaches the practical limit of impulse noise measurement capability inherent in most modern sound level meters.