Revised rule January 2016: From 1 January 2016 the use of muzzle brakes will not be allowed on shooting ranges where organised branch-, regional- or national shooting exercises/competitions are hosted by the branches of SAHGCA on the strength of the “SAHGCA Universal Rules at shooting exercises”.
Reasons for this decision: From the research done by the national Shooting Committee it is clear that a muzzle brake on a firearm on a shooting range where shottists shoot close to each other can result in serious problems regarding injuries and permanent hearing loss. Shottists in close proximity to a firearm equipped with a muzzle brake are exposed to unacceptable levels of noise, muzzle blast and even objects like sand, shrapnel, unburned propellant etc that are being propelled back in the direction of neighbouring shottisits. The sound by most muzzle brakes is more than twice as loud in comparison with the same firearm without a muzzle brake. The implication is that standard ear protection is usually not sufficient to protect shottists ears in the neighbourhood of firearms with muzzle brakes.
Hunters have a responsibility and are requested to be considerate and extremely careful when hunting with firearms equipped with muzzle brakes and to ensure that guides, hunting partners and bystanders are not exposed unnecessarily to the harmfull effects of muzzle brakes on firearms. A negligent shot in close proximity to an unsuspecting person without proper hearing protection can cause irreparable damage to for example the persons hearing.
Read Ron Thomsons’ book “Mahohboh” where he describes a real life hunting story about the disastrous effects of a muzzle blast on a fellow hunter in a close encounter with dangerous game….. An extract of this story is available at the bottom of this article.
The following are only excerpts from articles regarding research
on muzzle brakes and I invite you to follow the links provided to
read the ful length articles. These articles are published with
acknowledgment to the authors thereof:
Article 1: “Muzzle Brakes: Recoil reduction” by Cal Zant
However, in the section on muzzle devices from Dr. Carlucci’s textbook, Ballistics: Theory and Design of Guns and Ammunition, he reminds us “Best design practice is to divert gases to the sides of the weapon, because rearward diversion could affect an exposed gun crew.” During my tests, a manufacturer sent me a prototype of a muzzle brake with 45° baffles back toward the shooter. It provided outstanding recoil reduction (better than anything shown here), but while testing that brake, a friend helping me with the tests caught some shrapnel in his side. It penetrated 2 shirts and caused a wound deep enough to see flesh. I told the manufacturer I wouldn’t write about it, because I didn’t think it was safe. They were concerned as well, and haven’t release that prototype for sale.
The other downside of angled port designs is increased concussion/blast. All of the muzzle brakes are loud, but diverting gases rearward can increase the pressure shock wave at or near the shooter’s position. Some shooters would rather deal with the extra recoil than the increased concussion from that shock wave. So that is another thing to keep in mind. The sound test should give us insight into the pressure difference at the shooter’s position for each brake, so stay tuned for that.
There are clearly downsides to rearward deflection of gases, but it also has a measurable influence on recoil reduction. I don’t want to present this as “right or wrong.” It’s up to each shooter to strike the right balance for their application. I’m just trying to give a balanced and responsible presentation of all the facts to help you make an informed decision.
Article 2: “Muzzle Brakes: Sound Test” by Cal Zant
Both OSHA and MIL-STD-1474E require hearing protection if sound pressure levels are 140 dB or more (for “impulse” noises like gunfire). However, hearing loss can occur from sounds as low as 85 decibels with long or repeated exposure. Noise-induced hearing loss is cumulative and permanent. Ear protection typically reduces noise by 16-30 dB, which you can find by looking at their Noise Reduction Rating (NRR). For example, the popular Howard Leight ear muffs have an NRR of 22 dB. That may not get you below that 140 mark without “doubling-up” by wearing ear plugs in addition to the muffs. If you’re using a brake, please protect your ears, and pass that message on to your shooting buddies.
If we just start at the top, you can see the OPS muzzle brake was the “quietest” of the batch. It says “+ 41%”, which means it’s still 41% louder than the same rifle without a brake.
If you’ll remember, the OPS brake was also the worst performer when it came to recoil reduction … so I’m glad to see it wasn’t both ineffective and loud.
Most brakes hovered around 100%, which means they sound twice as loud as the rifle with a bare muzzle.
Finally, we have some brakes that were more than twice as loud. We see some familiar names at the bottom of this chart: APA Fat B* and Little B* Brakes, the Alamo Four Star Muzzle Brake, the Holland Radial Quick Discharge Muzzle Brake, and the Impact Precision Muzzle Brake. If you’ll remember, those were some of the best performers when it came to recoil reduction.
There seems to be a correlation between how loud a brake is, and how well it reduces recoil. Most “quieter” brakes aren’t good at reducing recoil, and most of the brakes that are great at reducing recoil are very loud.
|Extract – Real life story about muzzle breaks – Ron Thomson||22.24 KB|