How do Muzzle Brakes work? What is the best muzzle brake?
All you want to know about brakes and compensators: How do muzzle brakes work? What’s the best muzzle brake? Common myths.
The best muzzle brake for you depends on what you what it to do. If you want to know how to pick good one, read on.
Muzzle brakes work by redirecting gases (blast) to counteract recoil and reduce muzzle rise and ideally return the sight picture to its undisturbed view (zero) as quickly as possible. The words Brake and Compensator are usually used interchangeably, but to be strict, brakes reduce recoil and compensators reduce muzzle rise. Very few brakes can do it all and, those that do pick a sweet spot of combination of best factors, but may not be the absolute best in every parameter.
There are three basic designs and countless variation on them. Reverse Gill brakes have ports or “gills” that are angled back pushing blast toward the operator. Linear dynamics brakes more or less have cascading features that project blast forward. Radial design brakes direct blast at roughly 90 degrees to axis of the operator. Different designs have nuances that are best understood by learning about what is commonly misunderstood.
Myth: Compensators are loud and have harsh blast, and some so bad as to be unusable. Partly true. First distinguish between sound loudness (high decibels) and concussion or blast. Sound (loudness) from compensators are medium to high frequency sound (vibration) waves without much atmospheric displacement of gas and can be perceived as very loud. Concussion or blast are very low frequency waves that move so much gas that they can be perceived in your gut and can actually blow light objects away. They do NOT correlate with each other. That is a very loud brake can have low concussion and vice versa.
Although most compensators are loud (decibels), some are actually quieter than a bare muzzle. They accomplish this by “noise cancellation”. Some of the sound waves are canceled by mixing the vibrations “inside” the compensator to reduce noise, something like a noise canceling headphone,except the sounds waves mechanically rather than electrically partially cancel each other. This is achieved by proper acoustic design of mixing chambers. The trick is to have gases and sound mix inside the brake, without affecting accuracy. Even though these type of brakes diminish sound, they are not quiet. Distinguish this beneficial design effect, from a sound suppressor that uses a totally different method of encasing with sound deadening materials and complex baffles. Sound suppressors require tax stamps.
True, All compensators will have blast, some more than others. However it is the direction of blast that makes all the difference to the shooter. Brakes that use reverse gills are very effective at reducing recoil (rear impulse) but increase blast towards the operator, making them unpleasant, and decrease accuracy. They may or may not come back to zero quickly. Linear brakes direct the blast forward making decreasing blast to shooter and those nearby but decrease accuracy and don’t return to zero quickly. The best brakes will direct the blast at 90 degrees from muzzle making blast virtually undetectable for shooter but can make it significantly unpleasant for those at a 9 or 3 o’clock from firearm.
Myth: Muzzle Brakes suppress flash and flash suppressors reduce recoil. False. Flash suppressors like a basic A2 birdcage reduce flash by discouraging ignition of unburned powder. Flash suppressors don’t have much muzzle control. Some brakes will reduce flash but a well-designed brake will not reduce flash much as the way it works is by redirecting gas (which will contain unburned powder). It is possible to have one muzzle device do both if it is a two stage design. The first stage being the brake and the farthest end away from muzzle reducing flash. These will only partially reduce flash seen from 3 and 9 o’clock but do a better job as seen from 12 o’clock.
Myth: All Compensators reduce accuracy. Partly True. Most compensators reduce accuracy, but not all do. Brakes with Reverse gills and those with linear dynamics will definitely affect accuracy. Some brakes with radial dynamics will not. The reason for decreased accuracy is that some hypersonic gases will precede the projectile as it exits the crown of muzzle. Most brakes, especially reverse gill and linear dynamic brakes, create turbulence that will buffet the projectile slightly as it traverses the exit turbulence just past the muzzle crown. A properly designed radial brake will direct the gases AWAY from the projectile path yielding a very slight non turbulent vacuum to allow the bullet to pass undisturbed. Very few brakes have this design feature.
A totally different way brakes reduce accuracy is if the axis of the brake bore is not perfectly aligned with the barrel bore (Concentricity error). In the worst case, the projectile actually strikes the brake. In milder cases, the bullet is closer to one side of brake than other causing asymmetric turbulence. Lack of concentricity is usually caused by poor barrel threads or brake threads that are not perfectly concentric. Cheaper American barrels have this problem and most European AK variants are notorious for this because of poor quality control. That is why most AK brakes have a much larger brake exit hole to accommodate for this. Another cause of poor concentricity is imperfect brake threads. In order to ensure perfect concentricity, the threads must be cut with brake perfectly aligned, best done while brake is still in lathe. However, most brakes are cut with inexpensive manufacturing process by cutting threads with a single pass course die, similar to what a pipefitter uses. The best way to ensure perfect concentricity is multiple pass single contact threading but this requires better machinery and more machine time, read more costly.
Brakes are like other precision firearms parts, you usually don’t get more than you pay for.
Myth: Brakes wear out. Partly true. Some brakes with thin gauge metal are easily damaged and do wear out with time. Also those with small slits or ports tend to get fouled and self-destruct or decrease accuracy overtime.
Uncoated Titanium brakes although much lighter and stronger than steel will spark with hot loads and eventually the bore will widen. This will NOT cause brake to fail, but only to minimally loose effectiveness over time. One has to shoot LOTS of loads to notice a difference. This is not a factor for most Titanium shooters. Very Hard coatings like PVD, aka “Diamond Coating”, of Titanium brakes will mitigate this.
Cheap brakes with mystery metal like many copies from China can catastrophically fail in a dangerous way. Avoid these.
However, Brakes with enough beef, with hardened high quality steels properly coated will outlast you or your kit. There are a few brands that are noted for NEVER FAILING.
So how do you choose?
If you are a bolt action guy and want long range accuracy without beating up your shoulder, you will likely want a radial design. If you are semiauto guy who puts in a lots of heavy rounds at short range, a reverse gill or radial will work for you. If you are concerned about perceived operator blast, choose radial. If you are concerned about side blast to othes at 3 and 9 o'clock and don’t care about long range accuracy, or rapid return to zero get a linear design. If you want the best combination of all factors choose a radial design.
If you are a tactical guy or want to see your impacts thru scope pick a brake that returns to zero rapidly and has minimal muzzle rise, like radial design. Or if you anticipate combat or self-defense, and failure is not an option, this will usually mean a heavy duty beefy radial design with large non fouling ports.