What Is Paradox Rifling? What You Need to Know about Paradox Rifling

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The type of projectile you can shoot from a shotgun, rifle, or hybrid of both is determined by barrel rifling. These are the machined helical grooves within the gun’s barrel internal surface or bore. But what is paradox rifling, and which type of firearm and ammunition would be compatible with such a barrel?

Paradox rifling can be seen in a barrel, spreader, or choke tube that features rifling only at the end of the tube near the muzzle. This term emerged from 19th-century customization of a double-barreled shotgun when one fired shells and the other bullets. In 1885, a British colonel invented a ‘paradox gun,’ where the barrel, primarily smoothbore, would have the last few inches rifled in ratchet design.

It could be like the huntsmen of old: You’re tired of toting a shotgun for fowl together with a rifle for opportunist game or protection against predators like bears. Paradox barrels or chokes can provide lighter baggage as you won’t rely on two firearms. Learn more about this curious adaptation and its application today for hunters and shooters.

Does Paradox Rifling Make a Shotgun That Shoots Slugs Practical?

You’ve heard of gun bearers, expert firearm handlers that stood beside gentry hunters during their safari expeditions. Before Lt. Colonel George Vincent Fosbery came up with the paradox barrel, a shooter’s itinerary would include several rifles of various calibers, managed by several assistants. The entourage harvested small game like rabbits and fowl using a shotgun but would switch to rifles for larger or further away targets.

In 1886, Holland and Holland, English firearm manufacturers, started offering the double-barreled paradox gun after purchasing the patent rights. ‘Paradox’ in itself means a statement that stands in self-contradiction. Since smoothbore was the norm back then, this shotgun with a rifled barrel was contradictory to the status quo.

From hence, hunters to India and Africa could carry one firearm that uses two different projectiles. The shooter loaded the correct cartridge depending on the target and proceeded to shoot with conservative accuracy for both shells and slugs. By 1930, Holland and Holland had built over 1500 guns in various gauges or bore sizes. These included eight, ten, twelve, sixteen, and twenty-gauge.

The paradox gun also raised a legal question since any firearm with an over .50-inch rifled barrel regarded as a destructive weapon. A ruling by the Alcohol, Tobacco, and Firearms Bureau of that time, or BATFE, was obtained to state that since the gun fired shot-shells with a modification to shoot slugs, it was still a shotgun.

How Effective Is Paradox Rifling in Barrels or Choke Tubes for Hunters?

You can find paradox rifling already installed in single-shot break-open and bolt action shotguns. These firearms are remarkably accurate. For bullets, saboted slugs specially designed for a rifled barrel can shoot at par with a typical rifle.

Despite owning the patent and paradox gun trademark, other manufacturers also pitched into Holland and Holland’s dual-use, ball and shot firearm. Such replications of the original went by these makers’ brand names, including G and S Holloway and Westley Richard. By 1905, guns under trademark names like ‘Fauneta,’ a 20 to 28 gauge model, and ‘Explora,’ a larger 12-gauge firearm, were on the market in London.

With a paradox gun, a hunter can harvest small game and use paradox cartridges when deer opportunities present themselves. Paradox rifling can be part of the barrel or a small choke added to your smoothbore shotgun’s muzzle. With such a set-up, you’ll have an advantage over a shell or slug-only barrel regarding employing both for pests and big game.

In areas where fowl and deer seasons overlap, you can load up your firearm with shot, solid or hollow point rounds with varied results. Currently, Holland and Holland have a cartridge loaded with solid lead 740 grain.

How Are Barrels Rifled?

Various countries have developed forms of rifling, many originating from the time of muzzleloaders. Breechloaders also brought across multiple grooving patterns, and much of what we see today are copies of these designs. The 5R rifling is a famous example originating from the ’80s from the barrel maker Boots Obermeyer shop floor in Bristol, Wisconsin.

Instead of parallel sides, there are sloped and angular grooves that go top to bottom. The idea was sourced from the Russians with the AK-74 in 5.45x3mm. However, its origins are based on attempts to reduce black powder fouling accumulation in the 1700s.

Rifling in barrels is created by single-point or cutting methods, where one groove is made at a time or broaching. Progressive-broach tools cut them all at once. Pressing or button rifling involves punching all tracks with an implement named a ‘button’ inserted into the barrel. Hammer forging uses a mandrel containing a rifled reverse image, which is also used in the flow forming rifling method.

Machined metal plates are grooved and then twisted to form the inner bore of a rifled barrel; while laser etching employs heat or chemical reaction to etch the pattern. Paradox barrels and choke tubes are made from 42CrMo4 alloy steel and then coated in Nickel with DLC Brushed Chrome.

Examples of Rifling Patterns You Expect To Find In Paradox Shotgun Barrels

The idea of cutting grooves inside a gun bore originated during the later 15th, early 16th centuries in central Europe. At first, musket makers believed that straight grooves eased pushing the ball down the barrel of a muzzleloader when loading; and black powder could find places to accumulate. They intended to improve the uniformity of shot pattern while arresting slug spin or plastic wad columns traveling down the bore.

While not widely accepted by shooters, sub-gauge inserts for Briley over-under shotgun barrels have recently featured straight-groove rifling. Despite this disdain by clay target shooters and hunters, straight-grooving is evident in Franklin Armory’s Reformation rifle, an AR-15 chambered in .223 Remington.

To give projectiles improved accuracy and accommodate their various shapes, spiraled, twisted, and arrow fletching rifling was discovered. Accomplishing slug spin was arrived at with either groove accepting the exact size of round or hexagonal spiral-shaped grooving. However, each hard black powder fouling shot made it increasingly difficult to push musket balls down these muzzleloaders.

Throughout modern firearm history, some notable types of barrel rifling include;

Brunswick Rifling: 

Used in military muzzleloaders, Brunswick rifling featured two deep grooves. The belt on the projectile fits closely to these grooves; but aligning the two proved hectic and inefficient in combat situations.

Hexagon Style: 

The six-sided hexagon was a muzzleloader barrel rifling style used with a conical bullet. This design worked fine until fouling by the black powder made loading the slug down the bore difficult.

5R Rifling: 

Designed and created by Boots Obermeyer, this style combined the old five grooves with slope-sided lands. Adopted from an AK-74 rifle he saw, Obermeyer’s 5R is still used with many barrel makers.


One of the earliest forms of effective rifling, proven to be as effective as 5R, consists of five grooves with five lands.

Micro-Groove Rifling: 

Marlin developed this rifling with 12 grooves and lands that prove accurate for .30-30 and similar hunting cartridges. However, the life expectancy of accuracy diminished after 500 rounds, especially in the marlin model 322 bolt action chambered in .222 Remington.

Obermeyer’s Rifling

Obermeyer’s rifling, characterized by a fifth groove, was also adopted by the Lee Enfield .303 caliber rifles used by the British. This same pattern is similar to the 1917 Enfield used by the US and chambered in .30-06.

The land was positioned opposite the groove to lessen slug jacket deformation and reduced rapture possibilities for thin-jacketed match rounds in quick-twist barrels. 5R rifling varies considerably in accuracy and quality depending on the barrel manufacturer or licensed producer.

What’s More Effective, Paradox Rifled Barrels or Choke Tubes?

The first paradox rifled barrels for shotguns were attached to the firearm, thus necessitating a double-barreled combination. A smoothbore shot-shell barrel with a bead sight was for shooting small and moving prey; while the one outfitted with rifling used a rifle sight for still targets.

An alternative to a dual-barrel situation would be to have an exchangeable paradox alongside the smoothbore. It’s common to change over barrels for a single shotgun without tools in less than one minute. That way, a gun is used for fowling, trap, or skeet shooting and, with a rifled barrel, big game at over 100-yard ranges.

A great example is the Hastings Paradox replacement barrel that’s designed to fit many popular guns. In 20 gauge 1 in a 26-inch twist and 12 gauge 1 in a 34-inch twist, you can leverage its increased slug accuracy and stability. Such a barrel is available for browning A5 12 gauge, Remington model 870 12 and 20 gauge, and 1100 12 and 20 gauge shotguns.

A rifled choke tube provides a better solution for any gun barrel designed with a compatible muzzle. The last two or three inches of your shotgun will be rifled to impart some spin to your bullet.

Twist Rates for Barrels or Chokes in Paradox Rifling

Twist rate is the distance a slug travels inside the bore of a barrel before making one full rotation. In the mid-1800s, lead ball projectiles required little spin, as slow as 72 inches per turn or 1:72. That’s less than one rotation on a ball’s journey through the 30-inch barrels of the day.

Standardization came after 30 years, particularly for the Hawken brothers’ rocky mountain rifles of that era. The twist rate for musket or muzzleloader patched balls in .50 caliber is 1:48.

Since the paradox doubles by Holland and Holland, repeating shotgun barrels have enjoyed bore and screw-in rifling in the form of readily available chokes. Short-range bird guns are transformed into deer harvesters with considerable distance accuracy.

Progressive or gain twist rifling starts with a slow twist rate and increases gradually along the bore’s length. With reduced angular momentum of the projectile on the first few inches of the barrel, there’s less slug deformation when it enters the barrel’s throat.

Today’s efforts in barrel rifling are geared towards eliminating the sharp corner at the junction where each groove and land meet. By smoothing down the bore finish, acute-corner removal reduces bullet jacket fouling or smokeless propellant accumulation. The bullet obturates fully, which prevents the escape of propellant gas during slug and rifling engagement.


A unique ability to shoot shotgun shells and bullets is a paradox made a reality by rifling the barrel’s last two or three inches. At the same time, the ultimate in intrepid shot-choice, accuracy, and rifle-power work well with a shotgun’s lighter weight.

You can retain the intuitive ease of handling a shotgun while increasing versatility for less-fast-moving animals. If you are a hunter who travels in-woods for feathered or furred prey, paradox rifling, in barrel or choke-tube will offer a dual-functionality that’s addictive. 

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