Indians For Guns

Does Barrel Length Matter for a Home-Defense Shotgun?

by Evan Brune - Friday, June 16, 2017



When it comes to choosing a firearm for home defense, debate continues over the best possible choice, whether it be a handgun, AR-15 or a shotgun. However, the 12-gauge home-defense shotgun loaded with 00 buckshot has long been a mainstay of the homeowner’s defensive arsenal, and it continues to be popular.

Currently, the marketplace of 12-gauge home-defense and tactical shotguns is changing. For years, the 18.5-inch pump-action, home-defense shotgun was a go-to, and there were many options on the market from Mossberg, Winchester, Stoeger, Savage Arms and others. Now, the dynamic has changed with the introduction of guns like the NFA-regulated Mossberg 590 AOW, the Mossberg Shockwave or the Remington 870 Tac-14.

This raised a few questions: When considering a home-defense shotgun, is there an ideal barrel length when using 00 buck? What kind of results do you get with different kinds of buckshot? What is the maximum range that buckshot can be used effectively and safely in each of these different guns? It was time for some testing.

For the guns, we chose some of the more novel recent introductions to the market: the Mossberg 590 AOW and the Shockwave. The other gun used is well-known mainstay of the tactical-shotgun world: the Mossberg 590A1. Using all Mossberg-manufactured shotguns allowed us to ensure similar manufacture and construction across the guns used in the test.


Two of the three guns tested are shown here, along with the test setup and the Hornady and Aguila ammunition.

The Mossberg 590 AOW features a barrel length of 10.25 inches, which is about as short as it gets for a 12-gauge shotgun. Next up was the non-NFA Mossberg Shockwave, which features a 14-inch barrel. The Mossberg 590A1 uses an 18.5-inch barrel. Each gun was chambered in 12 gauge and featured a cylinder-bore choke.

For ammunition, we chose options from both ends of the personal-defense spectrum. The Hornady Critical Defense 00 Buckshot is a popular option for home defense and packs a punch, delivering eight 00 pellets at 1,600 fps, which makes for some devastating firepower. The MiniShell from Aguila Ammunition delivers seven pellets of No. 4 buck along with four pellets of No. 1 buck at an advertised velocity of 1,200 fps, providing a low-recoil option that can still stop a threat.

The test itself involved shooting each gun with each load at 7 yards, 15 yards and 25 yards. Five shots were taken at large sheets of white patterning paper while aiming at the same point, ensuring that a solid, measurable group was attained. The final group at each distance was then measured for overall diameter.

For safety and effectiveness, it is important that every shot fired hits the threat in a home-defense situation. Errant shots are out of the defender’s control, and those shots can end up harming family members in a different room or can pass through walls and harm passersby or neighbors. To simulate this, we consider it an effective and safe pattern as long as it falls within a standard IDPA torso size, which measures 18.125 inches wide.


All shot groups measured in inches.


The results we see above gave us some interesting conclusions. At 7 yards using the Aguila ammo, shots were surprisingly spread out, considering the short distances involved. The groups, measuring 13-14 inches, are dangerously close to exceeding our 18-inch maximum spread. Barrel length does not seem to matter much when considering across-the-room distances. From a 10-inch barrel to an 18.5-inch barrel, the spread only varied 2 inches.

The impact area of the Hornady Critical Defense was much different. This hard-hitting load exits the barrel at much higher velocities than the Aguila, producing tighter patterns downrange. Much like the Aguila, there wasn’t much difference between barrel lengths, with all shotguns producing groups in the 4.5- to 5.5-inch range.

One particular element to note is the varied difference between the Aguila and Hornady group sizes. This is evidence that ammo selection matters, because certain rounds will perform differently in the same firearm. Gun owners who select a shotgun for home defense will need to test their firearm with the ammo they intend to use to ensure that they are knowledgeable about its performance.


At 7 yards, there is a noticeable difference between the Aguila and the Hornady, but all shots landed within the prescribed 18-inch diameter.

This lesson was reinforced once we stepped back to 15 yards. At that distance, differences began to emerge between the different barrel lengths. With Aguila ammunition, the largest group was observed with the 10-inch Mossberg AOW, which produced a group that measured 36.75 inches.

However, there did not seem to be much measurable difference between the Shockwave and the Mossberg 590A1. Despite having more than 4 inches difference in barrel length, both guns produced groups that measured roughly 24.5 inches in diameter. However, all Aguila groups from all guns at 15 yards exceeded our ideal 18-inch maximum spread for safety and effectiveness.

The Hornady Critical Defense at 15 yards, like it did at 7 yards, provided a much tighter group than the Aguila. Like the Aguila, the 10-inch AOW provided the largest shot spread at 17 inches in diameter, while the 590A1 and the Shockwave produced similarly sized groups at roughly 7.5 inches. While all shot groups remained inside of our 18-inch maximum spread, the Critical Defense fired from the AOW comes dangerously close to exceeding that limit.

At 25 yards, all shots fired from all guns proved to be ineffective for meeting our 18-inch maximum diameter. It’s clear that, through cylinder-bore shotguns, these two particular ammo types are not meant for longer distances. For the Aguila in particular, safe and effective shot placement demands that shots not exceed 7 yards. The Hornady Critical Defense allows for safe and effective home-defense shots up to 15 yards with the right firearm when considering an 18-inch ideal target diameter.

Another important lesson from this test came from the use of a 22-inch barreled Winchester 1300. For unknown reasons that continue to stump Hornady engineers and NRA Publications editors, the 22-inch barreled Winchester produced large-diameter shot groups that, in some instances, exceeded those produced by the 10-inch Mossberg AOW.

The only clear fact to be learned from this is that some guns don’t mix well with certain kinds of ammo. That’s why it’s critical to always test a particular firearm/ammo combination at the range before counting on it for personal defense, regardless of whether it’s a handgun, rifle or shotgun.


Our testing involved shooting from a rest at a pre-marked aiming point to ensure as much consistency as possible.


Another important point to make about this particular test is that it is in no way definitive for any single individual’s home-defense shotgun. We based our target diameter on a standard IDPA target, but threats come in all shapes and sizes, and homes feature many different room sizes, hallway lengths and types of construction that warrant a customized look for the ideal home-defense shotgun.

Important point: Are there other people inside or outside your home who must be considered with regard to errant buckshot rounds? If so, it behooves shotgunners to minimize their total impact area on a target to prevent stray rounds from harming family members.

Other considerations include total shot distances inside of a home. Those with larger homes may be faced with the possibility of taking a shot at a distance of more than 15 yards. If this is a consideration, then experimenting with different ammo types or shotgun chokes may be necessary. Shotgun editor Jeff Johnston covered the use of shotgun chokes to control buckshot spread, and it is worth some experimentation with your particular shotgun.

Perhaps the biggest myth this particular test dispels is the idea that all home-defense shotguns, regardless of distance, ammo type or barrel length, do not require careful aiming to dispatch a threat. On the contrary, at shorter distances, shot sizes are measured in just a few inches, and sloppy aiming can cause a cluster of 00 buck to zip past an intruder without stopping the threat.

On the other side of the spectrum, larger shot groups also require careful center-mass aiming to ensure that all pellets impact the threat and provide maximum fight-stopping power while also avoiding the possible harm caused to bystanders by stray buckshot.

Above all else, this test shows that counting on Grandpa’s old double gun in the closet without ever firing a practice or patterning shot is a poor home-defense plan. Get on the range with a few shells and create your own patterning chart to see how your shotgun performs. Better yet: take shotgun-specific training with a reputable instructor.