12-Gauge vs 20-Gauge Shotguns: Does Size Matter?

Shotguns are some of the most popular firearms on the face of the planet. Their relatively simple designs make them ultra-reliable (especially if we’re talking double barrel break actions). Because shotguns can sling everything from tiny round pellets to hefty slugs, they are the jack-of-all-trades in the gun world. 

If you can only own one firearm (we offer our sincere condolences), it should probably be a do-it-all shotgun.

While shooters agree on the inherent versatility and utility of the common scattergun, there are always heated arguments about which one is better. The 12 gauge vs 20 gauge has certainly inspired its fair share of deep-camp shouting matches, bar-room brawls, broken friendships, and probably even a few divorces. 

We don’t expect this article to settle the disagreements once and for all. However, we are firm believers that knowledge is power. We don’t expect to sway any die-hard devotees, but hopefully, we’ll give you something to think about the next time you’re in the market for a new shotgun. 

THE NUMBERS GAME: SHOTGUN GAUGES 101

Scattergun numbers can be confusing, especially for the uninitiated. In the shotgun world, bigger numbers don’t mean bigger guns. It’s actually the opposite. A smaller number indicates a bigger bore.

Most shotgun bores are measured by “gauge.” The exception is the .410 bore which is measured in caliber because the shooting world likes to keep newbies guessing. 

The concept of gauges is a leftover from yesteryear when an average Joe would buy a pound of lead and use it to fashion his own ball ammo. If Joe was shooting a 12 gauge shotgun, he knew he could get exactly 12 projectiles the same size as his bore from that single block of metal. 

If we measured shotguns like rifles, a 12-gauge would be a  .729 caliber, because the bore measures .729 inches across. 

The bore of a 20 gauge measures a smaller .615 inches in diameter. 

THE SHOT-COUNT ADVANTAGE

There is a common misconception that the 12-gauge is ballistically superior to the 20-gauge. While the 12-gauge definitely holds a power advantage, it gains that advantage through sheer shot count, not velocity. 

A 12-gauge can be loaded to higher velocities (think magnum loads), but most 20-gauge loads push their pellets just as fast as standard 12-gauge shells. For example, Federal Premium’s Speed Shok #1 steel loads in 12 gauge and 20 gauge both produce a muzzle velocity of 1550 fps. 

The secret to the 12-gauge’s power lies in its shell capacity. A 12-gauge shell holds more (and sometimes larger) shot. 

Federal’s heaviest 20-gauge payload is only 1 ⅝ ounces (in Heavyweight TSS) compared to the 2 ½ ounces of lead packed into some of the company’s 12 gauge loads. 

More pellets traveling the same speed deliver more on-target energy. It’s not magic. It’s physics.  

SHOT PATTERNS

As soon as shotgun pellets leave the muzzle, they begin to fan out in a cone. Although using a choke can help constrict the pattern, chokes can only do so much. Even with a full choke, the spray of pellets gradually gets larger as it travels downrange. 

Think of shot spread like the spray setting on a garden hose. The closer you are to the nozzle, the tighter the water spray.

As you move further away from the hose, the water droplets spread out. Get far enough away, and the gaps between the water droplets widen until maybe only a few hit you.

Shotguns aren’t garden hoses, but this should help get the point across. 

However, shotguns do spray pellets, sometimes at small, fast-moving targets. The gaps between the pellets in your spay don’t have to be massive for a small dove or bobwhite to slip through unscathed. 

One easy way to narrow the gaps between your pellets is to send more of them downrange. 

Enter the 12-gauge with its heavier payloads and greater shot count. More pellets deliver denser shot patterns and a longer effective range. 

Can you shoot clays or hunt deer/turkeys/waterfowl/upland birds with a 20 gauge and its lighter payloads? Absolutely. You just need to be a little more careful with your range and shot placement.

RECOIL ENERGY

Heavier payloads require more powder to drive them downrange at an effective speed. While the 12-gauge has a pellet count and pattern density advantage, that performance comes at a price. 

Recoil.

It’s the “equal and opposite reaction” Newton warned us about in his Third Law of Motion.

The 20-gauge has a reputation for producing less felt recoil than its big brother. It’s the main reason 20 gauges are often handed to the youngest hunters. 

However, the difference in recoil between these two scatterguns isn’t as severe as you might think.

12-gauge loads leave the muzzle with more energy than comparable 20-gauge loads, which means they should have a softer kick. Right?

Not necessarily. A ton of recoil energy is absorbed by your gun, which means it never makes it to your shoulder. Since most 20 gauge shotguns are lightweight models, there isn’t as much gun there to soak up that energy. Shaving a half pound off a 20 gauge leaves you with felt recoil that isn’t much milder than what a heavier 12 gauge punches. 

Run some buckshot with the same payload through two pump actions, and your shoulder probably won’t be able to tell the difference between the 12 gauge and 20 gauge. 

However, shooting lighter payloads reduces recoil, and since most 20-gauge loads feature lighter shot charges, they tend to be more kind in the recoil department. 

SHOOTABILITY

Although the lighter design of the average 20-gauge scattergun may not do our shoulders any big favors, that design pays big in shootability.

Not only are the compact 20-gauge featherweights easier to tote when chasing thunder chickens through thick woods, but they are also easier to maneuver, especially within the tight confines of a duck blind. 

That doesn’t mean you can’t find lightweight 12-gauge scatterguns that make trekking through acres of prime pheasant territory less tiring. It just means your shoulder might need a good slathering of Tiger Balm when the hunt is over. 

Versatility

Shotguns are versatile weapons. All of them.

While both 12- and 20-gauge shotguns are great all-around firearms, the 12-gauge just barely noses out its little brother in the versatility department.

With its larger diameter, 12-gauge shells can hold bigger projectiles. 20-gauge shells usually max out with #3 buckshot. There just isn’t enough room in there for anything bigger. 

12-gauge loads offer options for larger buckshot and heavier slugs. 

You can use a 20-gauge to shoot pretty much everything you can shoot with a 12-gauge. However, the 12-gauge’s lasting and booming popularity will provide a wider array of ammo options to choose from. 

CHOOSING THE BEST SHOTGUN

If you’re in the market for a new scattergun, you’re in luck. There is no shortage of options for either 12- or 20-gauges.

Here are a few awesome, all-purpose shotguns that should be near the top of your list. 

Mossberg 500

The Mossberg 500 is one of the most iconic shotguns to ever grace a trap field, duck blind, or the turkey woods. One of the best-selling shotguns of all time, this model sets the bar for pump-action shotguns, and that bar is incredibly high.

The Model 500 is available in more than a dozen variations, with models that cater to turkey hunters, law enforcement, home defense, and youth shooters. 

The models vary in barrel length, stock material, length of pull, choke options, magazine capacity, and bore size, but they all share the same rugged, reliable action and receiver. 20-gauge M500s are just as rugged and reliable as the 12-gauge versions, so you can’t go wrong with either one. 

Browning Citori

Over/Under shotguns are often chided by shooters who value technology and magazine capacity above all else. However, these classic shotguns have a refined style that is unmatched in the shotgun world.

O/U shotguns, like the Browning Citori, are the most reliable scatterguns on Planet Earth. They never jam, you can’t short-stroke them, and they will eat whatever ammo you feed them.

These guns also last for hundreds of thousands of rounds. Your great-great-great-grandchildren will still be busting clays and popping birds with this gun 100 years from now, whether the bore size is 20- or 12-gauge. 

Benelli Super Black Eagle 3

If you’ve got a few extra Franklins in your shotgun budget, and you enjoy slinging shotshells semi-auto style, the Benelli Super Eagle should make your shortlist. Both the 12-gauge and 20-gauge versions are top-notch.  

We admit this gun has a ridiculous name, but what Benelli lacks in creativity, it more than makes up for in its design. Benelli’s unique inertia action is simple and surprisingly reliable for a semi-automatic. 

Plus, this gun handles like a dream, and when loaded with TSS, it stretches effective waterfowl ranges like your grandma could stretch a dollar during the Great Depression.  

LOOSE ROUNDS

One of the reasons we love shotguns is their incredible versatility. There’s no other single gun you can use to hunt everything from tiny woodcocks to big bruins effectively. 

When it comes to home protection, a trusty shotgun is just as effective on slithering snakes as it is on two-legged predators. 

Having a shotgun hanging over the mantle (even if it is hanging there figuratively, because of modern safe storage laws) is far more important than the gauge of that smoothbore.