Today’s feature comes to us from our companion service, Shooting News Weekly. All images provided by Travis Pike.

For years, the 20 gauge has been considered a practical alternative to the 12 gauge, offering lower recoil and substantial power. However, finding a purpose-built tactical or defensive 20 gauge shotgun has been a challenge.

While 20 gauge deer and bird guns are plentiful, a dedicated tactical smoothbore has been…elusive. Until now, that is. Mossberg has introduced both .410 and 20 gauge variants of their renowned 590 series pump guns, each with unique features that address this long-standing issue.

It’s worth mentioning that Mossberg used the 590 platform to create both .410 and 20 gauge Shockwaves and simply extended those into proper shotguns. There are two variants of the 20 gauge model. There’s my plain-Jane model and an SPX-type gun with ghost ring sights. My plane-Jain gun holds six rounds in the tube and one in the pipe with an 18.5-inch barrel. The SPX gives you nine shots and a 20-inch barrel.

Why the 20 Gauge?

I love shotguns, but almost all of my experience has been with 12 gauges. Diving into 20-gauge guns gave me a better perspective on using one for home defense. As a man with a broken shoulder, I suspect I’ll be forced to switch to the 20-gauge eventually, so I might as well get educated now.

The 20 gauge 590 shotgun was like a crash course and I was impressed. The first thing I did was look for quality defensive ammo.

A 20 gauge 590, who would-a thunk it?

When it comes to tactically inclined defensive 20 gauge ammo, the options are limited, often leaving you with sporting rounds of buckshot. At SHOT 2024, Federal’s announcement of a Flitecontrol load for the 20 gauge caught my attention, but it’s yet to hit the market. (Trust me, I email Federal once a month about it.)

Barnes and Winchester make ‘tactical’ 20 gauge loads, but they don’t offer anything particularly unique other than a high price point.

There are plenty of #3 and #2 buckshot loads out there, but I had a lot of success with Monarch 9-pellet #1 loads. In the past, #1 buckshot has proven to be a capable penetrator, and nine pellets provide a decent payload that’s on par with your average 00 12 gauge load. The patterns are tight, and the recoil is, at worst, mild.

The Mossberg 20 Gauge 590 is identical to its 12 gauge counterparts.

The 20 gauge provides something of a Goldilocks option. It’s so powerful as to create excessive recoil, and it’s not so underpowered that you lose out on the advantages of a defensive shotgun. It’s just right for the shotgunner who can’t deal with the oomph of 12-gauge recoil, but still wants that efficient multiple pellets-per-trigger-pull effect.

The 20 Gauge 590

As a man who already appreciated Mossy shotguns, the 20-gauge 590 wasn’t a big surprise. It’s identical to their 12-gauge variants. The controls and ergonomics are the same. The pump is still a little sloppy, and the trigger is a little mushy, but that’s all normal for a 590. The tang safety is right where you want it, and the bead sits directly on the barrel.

The tang safety is brilliant…always has been, always will be.

I can’t speak for all furniture, but most stocks for the 12 gauge will fit the 20 gauge. Others might not have the same level of compatibility, but GG&G modifies the Magpul MOE forend to work on 20 gauges if you’re hard-up for M-LOK slots. Sadly, none of the built-in weapon light forends from Surefire, Streamlight, or Nightstick fit the 20 gauge variant. You’ll have to be more creative with weapon lights.

The 20 Gauge 590 is simple, but still carries the genes of a fighting shotgun.

The 20 gauge 590 features a drilled and tapped receiver for optics. I had a Williams Gun Sight LRS mounted, but I’m currently experimenting with others. (That’s why there’s still a mount on the receiver.) Red dots on shotguns are like peanut butter and jelly…they go together well for instinctive, quick-reaction shooting.

The 20-gauge 590 shotgun differs from the standard 590 in that it weighs only seven pounds. Oh man, I love how little this shotgun weighs. That light weight makes the gun super handy and easy to tote. I never considered the considerable weight savings just a few pounds make.

The Mossberg 590’s cleanout tube is one of the big distinguishing features of the 590.

It’s great as a lightweight working gun and a home defense firearm. If you need to release the 20 gauge 590 with your support hand for some other task, you can still keep the gun forward and toward a threat’s direction.

Pumping and Shucking With the 590 20 Gauge

Right off the bat, the difference in recoil between the 20 gauge and 12 gauge is significant. I’m pretty good at the push/pull technique of recoil mitigation, and with that technique, I don’t even have to shoulder the 20 gauge 590 to tame the gun.

I ran through a few drills, including two-round strings at ten yards with buckshot. I landed two rounds on target in exactly one second. That’s blazing fast, and I’m proud of it. I ran through the shotgun casino drill and the shotgun el pres. This is where I ran into some interesting bugs with the 20 gauge 590.

Loading the 20 gauge tube isn’t as easy as loading the 12 gauge tube. There’s a little extra room inside the loading port, and when trying to press a round into the magazine tube, it occasionally got stuck on the inside of the loading port on a portion of the receiver that surrounds the tube. It’s less intuitive than the 12 gauge, but won’t slow you down considerably.

At 10 yards, the gun patterned my Monarch nine-pellet buckshot load in a pattern roughly the size of my palm. I fired five rounds and the patterns consistently measured between 4.3 and 5 inches. That’s not terrible. It’s not FliteControl good, but it’s tight enough for home defense use.

The 20-gauge 590 runs like a pump shotgun should. It always goes bang, extracts empties, and ejects them. Bottom line: Mossberg’s 590 shotguns set the standard for reliable pump action shotguns.

All Rainbows

The main problem I have with the 20-gauge 590 is the bead sitting on the barrel. With basic buckshot, that isn’t a big problem, but with slugs, the rounds all appear to hit high. Once the 20-gauge Flitecontrol load is finally released, I expect it will have the same problem slugs have at home defense ranges.

I wish Mossberg would raise that bead a bit like Remington does with their pedestal bead sight. Luckily, Defender Tactical has us covered with their HighBall bead sight. That fixes the issue and makes point of aim and point of impact the same.

Another issue is the 590’s stock has a length of pull of around 13.87 inches. That’s fine for me, but I’m a big guy. I’d bet a lot of people looking at 20-gauge guns are smaller shooters and would be better served by a more Bantam-length stock.

The Mossberg 20-gauge 590 is an outstanding 20-gauge option. The 590 has been a leader in the tactical pump-action world for decades and it’s about time they released a 20-gauge variant of the gun. Luckily, it lives up to the well-earned reputation Mossberg has established with the 590 series as a fighting shotgun.

Specifications:
Gauge: 20 Gauge
Action Type: Pump-Action
Chamber Size: 3″
Barrel Length: 18.5″
Choke: Cylinder Bore
Capacity: 6+1
Length: 39.5″
LOP: 13.87″
Weight: 7 pounds
MSRP: $566

— Travis Pike