In our Shooters’ Forum, there was an discussion about a range that was threatened with closure because rifle over-shoots were hitting a farm building over two miles from the firing line. One reader was skeptical of this, asking “how’s that possible — were these guys aiming at the stars?” Actually, you may be surprised. It doesn’t take much up-angle on a rifle to have a bullet land miles down-range. That’s why it’s so important that hunters and target shooters always orient their barrels in a safe direction (and angle). Shooters may not realize how much a small tilt of the barrel (above horizontal) can alter a bullet’s trajectory.
How many degrees of muzzle elevation do you think it would take to hit a barn at 3000 yards? Ten Degrees? Twenty Degrees? Actually the answer is much less — for a typical hunting cartridge, five to seven degrees of up-angle on the rifle is enough to create a trajectory that will have your bullet impacting at 3000 yards — that’s 1.7 miles away!
Five degrees isn’t much at all. Look at the diagram below. The angle actually displayed for the up-tilted rifle is a true 5.07 degrees (above horizontal). Using JBM Ballistics, we calculated 5.07° as the angle that would produce a 3000-yard impact with a 185gr .30-caliber bullet launched at 2850 fps MV. That would be a moderate “book load” for a .300 Win Mag deer rifle.
Here’s how we derived the angle value. Using Litz-derived BCs for a 185gr Berger Hunting VLD launched at 2850 fps, the drop at 3000 yards is 304.1 MOA (Minutes of Angle), assuming a 100-yard zero. This was calculated using a G7 BC with the JBM Ballistics Program. There are 60 MOA for each 1 degree of Angle. Thus, 304.1 MOA equals 5.068 degrees. So, that means that if you tilt up your muzzle just slightly over five degrees, your 185gr bullet (2850 fps MV) will impact 3000 yards down-range.
Figuring Trajectories with Different Bullets and MVs
If the bullet travels slower, or if you shoot a bullet with a lower BC, the angle elevation required for a 3000-yard impact goes up, but the principle is the same. Let’s say you have a 168gr HPBT MatchKing launched at 2750 fps MV from a .308 Winchester. (That’s a typical tactical load.) With a 100-yard zero, the total drop is 440.1 MOA, or 7.335 degrees. That’s more up-tilt than our example above, but seven degrees is still not that much, when you consider how a rifle might be handled during a negligent discharge. Think about a hunter getting into position for a prone shot. If careless, he could easily touch off the trigger with a muzzle up-angle of 10 degrees or more. Even when shooting from the bench, there is the possibility of discharging a rifle before the gun is leveled, sending the shot over the berm and, potentially, thousands of yards down-range.
Hopefully this article has shown folks that a very small amount of barrel elevation can make a huge difference in your bullet’s trajectory, and where it eventually lands. Nobody wants to put holes in a distant neighbor’s house, or worse yet, have the shot cause injury. Let’s go back to our original example of a 185gr bullet with a MV of 2850 fps. According to JBM, this projectile will still be traveling 687 fps at 3000 yards, with 193.7 ft/lbs of retained energy at that distance. That’s more than enough energy to be deadly.
Muzzle brakes are controversial. Some people swear by them, while others swear at them. Still, there’s no question that a good brake can reduce felt recoil up to 45%. And likewise, the best brakes, when installed properly, seem to have no negative effect on accuracy.
Roy Bertalotto has done considerable experimentation with muzzle brakes, testing dozens of brake designs on his own rifles over the past few years. Roy’s article, Adventures with Muzzle Brakes, discusses various aspects of muzzle brake design and performance. Roy doesn’t claim that his testing is definitive, but his article is definitely worth a read. Here are some of Roy’s interesting findings:
Exit Hole Diameter
“Best accuracy and effectiveness of the brake was obtained with a hole .020″ over bullet diameter. If the exit hole is too small, such as +.005″ over bullet diameter, accuracy suffers. If the depth of the exit hole is too shallow, the metal around the hole will erode very quickly.”
Hole Placement
“The most effective braking was with a brake 1″ in diameter with a 3/4″ exit hole on each side, just in front of the muzzle. The bullet passes through a cone of 35 degrees before it exits the brake. (Like the tank example), Incredible reduction of recoil. But loud and ugly. Very easy to make since you don’t need a spin fixture or a dividing head.”
Bottom Gas Venting Helps Accuracy
“In my tests, not having holes all around the brake effects accuracy a bit. I believe it does something to the bullet by the air pushed ahead of the bullet creating unequal turbulence in the bullet path. I’ve tried a few brakes where I drilled only holes on the top, test fired, and then completed holes on the bottom and in every case, accuracy improved.” Below are spiral-ported brakes crafted by Clay Spencer.
Brakes Work Best with High-Pressure Cartridges
“The higher the pressure of the particular round, the more effective the brake. I have over 20 rifles with brakes. The 220 Swift is the king of reduction. Followed very closely by the 25-06, 6mm Remington, any Weatherby small bore. With a proper brake and a hot handload under a 40 gr bullet, the Swift will move 1/2″ to the rear and 0 muzzle rise! Big boomers with low pressure like 45-70s and shot guns benefit the least.” [Editor’s Note: Roy is judging effectiveness by the percentage of recoil reduction rather than absolute levels of recoil. Obviously if you start with a heavier-recoiling round, the absolute amount of recoil energy reduction is greater. Roy is really talking about efficiency–brakes are most efficient when used with high-pressure cartridges.]
Installation is Key to Accuracy
Roy’s findings are fascinating and suggest that further study of muzzle brakes is warranted. But we can all agree that precision installation of the brake is essential for accuracy. A poorly-installed, mis-aligned brake will degrade accuracy, that is well-known.
Harrell’s Precision has made thousands of muzzle brakes, in many styles and port arrangements. The Harrell brothers offer some good advice for gunsmiths installing brakes: “Muzzle brakes aren’t magic, they reduce recoil by redirecting exiting gas. What’s important is that they are straight and the threads are perpendicular with the base. The only way to get the base and threads perpendicular is to thread, not tap, them on a lathe.”
Forum member Kenneth Skorpen (aka “Sal”) from Norway sells a variety of shooting products through the www.Vertebrae.no website. Among the more interesting products offered by Skorpen are a series of muzzle brakes that can be installed on your barrel with no gunsmithing required — if the barrel tip has already been threaded. Crafted in Norway by Vektor Maskin, these muzzle brakes employ an internal inside/outside threaded bushing with a stop nut that fits on the barrel. With the threaded bushing in place, you simply screw the muzzle brake onto the bushing, align it so the ports are horizontal, then set the stop nut and set-screws. (Note, the set-screws touch only the bushing — they do not impinge on the barrel itself.) The video below shows how Vektor spin-on muzzle brakes are installed:
There are compact, standard, and large size Vektor muzzle brakes. Adjustment and installation is the same for all three sizes. The small, compact model, with two rows of opposed horizontal ports, is designed for .223-caliber rifles. The medium (standard) size, with either double or triple sets of opposed ports, is suited for 6.5mm or .308 calibers. The largest size, with three rows of large ports, is configured for the .338 magnum calibers. Skorpen claims that all three sizes of Vektor brakes can reduce felt recoil by 70% to 80% The brake itself is SIS1914-04 steel with an oiled zinc phosphate finish. The internal socket is AISI 303 (SUS 303) stainless steel.
If your barrel is already threaded at the muzzle, the Vektor brakes can be installed with no metal-work or gunsmithing required. Otherwise, you will need a gunsmith to thread the muzzle end of the barrel. The Vector bushings can be machined to a variety of thread types: 1/2″-20/UNF, 1/2″-28, 5/8″-18/UNF, 5/8″-24, m14x1, m14x1.5, m15x1, m16x1, m17x1, and m18x1. Just indicate the thread pitch you require when ordering.
How to Order Vektor Muzzle Brakes
Skorpen’s company, Vertebrae Sikkerhet & Teknikk, exports these Vektor brakes at reasonable prices. With one (1) supplied bushing, the compact brake is $131.43 USD, standard brake is $167.64 USD, and the large (magnum) brake costs $198.49 USD. Extra bushings are available for around $20.00. While the website lists .223, 6.5mm, .308, and .338 caliber brakes, Vetebrae can produce brakes in other calibers on request (add 5 days to delivery time).
You can also purchase Vektor muzzle brakes by emailing joachim [at] vertebrae.no. (It may be cheaper to order direct via email.) Just send an email stating your desired caliber and thread pitch. Normal delivery time to the USA is one to two weeks.
In our Shooters’ Forum, there was an discussion about a range that was threatened with closure because rifle over-shoots were hitting a farm building over two miles from the firing line. One reader was skeptical of this, asking “how’s that possible — were these guys aiming at the stars?” Actually, you may be surprised. It doesn’t take much up-angle on a rifle to have a bullet land miles down-range. That’s why it’s so important that hunters and target shooters always orient their barrels in a safe direction (and angle). Shooters may not realize how much a small tilt of the barrel (above horizontal) can alter a bullet’s trajectory.
There are compact, standard, and large size Vektor muzzle brakes. Adjustment and installation is the same for all three sizes. The small, compact model, with two rows of opposed horizontal ports, is designed for .223-caliber rifles. The medium (standard) size, with either double or triple sets of opposed ports, is suited for 6.5mm or .308 calibers. The largest size, with three rows of large ports, is configured for the .338 magnum calibers. Skorpen claims that all three sizes of Vektor brakes can reduce felt recoil by 70% to 80% The brake itself is SIS1914-04 steel with an oiled zinc phosphate finish. The internal socket is 
