“Twelve or twenty?”
It’s the first thing out of almost everybody’s mouth when they come in looking for a house gun. It’s also about the fifth most important decision they’re going to make, and they’ll spend more time on it than on the four that matter. So let’s run the list backwards, starting with the one everybody wants to fight about.
The 12 throws more lead. A standard 2¾-inch load of 00 buck is nine pellets of .33 caliber, and that number is what the whole gauge argument is actually about. The 20 answers with something like #3 buck: more pellets, smaller, less total payload. On paper the 12 wins.
Off paper, the 20 is not the weak sister, and anybody who says it is has never watched a 140-pound shooter get beaten up by a 12 through a box of buckshot. A gun you flinch with is a gun you shoot badly, and a gun you shoot badly at two in the morning is a liability with a serial number. The recoil gap between the gauges is real and it isn’t small. Then add that reduced-recoil 12-gauge buckshot exists and is what most serious people load anyway, and the gap narrows from both ends. Pick the one you can hold on target for five fast rounds. That’s the entire test.
If you want to see what patterning actually looks like, Lucky Gunner shot the buckshot comparison so you don’t have to guess:
Pump or semi-auto is next, and here’s where the lore gets in the way.
Everybody knows a pump always works. What a pump actually does is move the reliability out of the gun and into your hands, which is a fine trade right up until your hands are full of adrenaline. Short-stroking — not running the forend all the way back, so the next shell never gets picked up — is the most common shotgun stoppage there is, and it isn’t a bad-shooter problem. It’s an unpracticed-shooter problem. The pump doesn’t delete the failure point. It relocates it into you.
That said, the case for one is still strong. It costs a third of what a good semi does, there’s almost nothing to maintain, and it’ll cycle whatever you feed it: full-power buck, reduced-recoil, cheap birdshot for practice, less-lethal if that’s your world. A gas gun needs loads with enough gas to run it, and the light target rounds you’d train with most are exactly the ones most likely to choke it.
Semis shoot softer and faster, which matters more the smaller you are. The Benelli and Beretta autoloaders that police and serious defensive shooters lean on earned their reputations honestly. They also start north of a thousand dollars, and a $1,400 semi you’ve never trained with loses to a $300 pump you’ve run a thousand times.
Now the part buyers genuinely underrate: the thing is long.
Federal law sets the floor at an 18-inch barrel and 26 inches overall, and your state may want more. That’s why security models ship with 18.5 inches of barrel — shortest legal length plus enough margin that nobody has to argue. It is still a long gun. Cut a broomstick to about 39 inches and walk your own hallway with it. Around the door frame. Past the stair rail. Into a bedroom with a kid behind you. That’s the test nobody runs before they buy, and it’ll tell you more than any spec sheet.
Stock length matters more than the catalogs let on, too. Factory stocks are cut for a large adult in a t-shirt. A shorter length of pull gets most people a consistent mount, and a consistent mount is where your pattern comes from.
Which brings us to the decision that actually is the decision: what’s in it.
Birdshot is not the safe answer. It’s the answer people reach for because it sounds gentler, and at across-the-bedroom distance it does ugly things. But the penetration standard everybody works from — the 12-to-18-inch gelatin benchmark the FBI settled on — is a benchmark because that’s the depth that reliably reaches what stops a fight, and birdshot doesn’t get there except at contact distance. It’s a bird load. The bird weighs eleven ounces.
Buckshot is the consensus and has been for fifty years. 00 or #1, reduced-recoil if your gun likes it, and the modern wad designs built to hold the pellet column together pattern dramatically tighter than the bargain stuff. That’s the one place in this whole conversation where spending more actually shows up on paper.
Slugs are the specialist’s answer — a barn, a treeline, a rural property where the shot might be sixty yards. Inside an apartment, a slug is a rifle bullet with a sense of humor about drywall.
And that’s the over-penetration conversation done honestly: nothing that works stops at a wall. Buckshot goes through interior walls. So does 9mm. So does .223, and so does everything else anyone has ever kept by a bed. The wallboard testing people have been publishing for twenty-odd years is boringly consistent on the point. Birdshot penetrates less, true — and it’s also the option that might fail to stop the problem in front of you while still hurting someone in the next room. That’s not a safety feature. That’s both failures at once.
The real answer to over-penetration was never a load anyway. It’s knowing your own floor plan: where the kids sleep, which wall you share with the neighbors, what angle keeps the bad outcome out of both. Plus the discipline never to fire at a sound. You can’t identify what you can’t see, which is why a light — on the gun or in the other hand — isn’t optional gear.
Then pattern the thing. Almost nobody does. It’s the most-skipped step in home defense and it takes twenty minutes.
Seven yards is a long shot inside most houses. Staple a paper plate to a backer, step off seven yards, fire five rounds of the exact load that lives in the gun. The old rule of thumb is roughly an inch of spread per yard, which would put you around seven inches at seven yards. Your gun and your load might throw four. Might throw fourteen. There is no way to know except to shoot it, and every pellet that leaves that paper belongs to you, legally and otherwise. Finding out afterward is the wrong time.
As for money, the sub-$400 pump class is genuinely good. Maverick’s 88 is Mossberg’s value line — crossbolt safety instead of the 500’s tang, its own trigger group, most everything else shared with the parent gun — and it’s the cheapest honest home-defense long gun in America. Step up to the Mossberg 500 or 590 and you get that tang safety, which is the best-placed safety on any long gun and works identically whether you’re right- or left-handed.
The 870 needs an asterisk, and this isn’t brand-bashing. Cerberus bought Remington in 2007 and ran it as Freedom Group, later Remington Outdoor. Bankruptcy in March 2018. Bankruptcy again in July 2020. Roundhill Group picked up the firearms business that September and runs it as RemArms, licensing the Remington name from the side of the breakup that got the ammunition plant. The Ilion, New York factory that built 870s for generations closed in March 2024. So “an 870” isn’t one product. A Wingmaster from 1978 and a gun from the middle of all that are different objects wearing the same rollmark. Work the action on the specific gun in front of you and buy that gun, not the name on it.
What more money buys is real: an autoloader that shoots softer, ghost-ring sights, a light mount that isn’t an afterthought, a trigger that doesn’t fight you. What it can’t buy you is the twenty minutes with the paper plate.
Which is the whole thing, really. The best home-defense shotgun on earth is the one you’ve actually patterned, the one you can load and run in the dark without looking at it, and the one you’ve already decided how to store. Because the gun locked in a safe you can’t open at 2 a.m. and the gun leaning in the closet where your nephew can reach it are both wrong answers, and that night is not when you get to work out which is which.
