Best AR Pistol Caliber For Home Defense

    Often times, I get questions from people about what would be the best caliber for ARs in the home. Typically, a handgun with some sort of flashlight or light/laser combo will be a better option since it’s easier to move with a handgun than with a large rifle. Handguns also give you a free hand if you have to grab your child and move them to safety.

    I get it’s a small detail but others have asked what they should be using when it comes to home defense. Most questions I get are from people wondering what caliber is the best for inside the home. I know some of you are saying just use a shotgun if you want a larger weapon and you’re not wrong. Having a shotgun in a self-defense situation is devastating at close range distances. Some people insist on running a rifle or AR-style set up though for various reasons. I don’t yuck other people’s yum, so let’s jump into the good and bad of AR self-defense in the home.

    Pistol Caliber Carbines

    Having a pistol caliber carbine or little AR pistol chambered in 9mm or 45 ACP isn’t a bad option for inside the home. Most times they are relatively light and maneuverable while having plenty of stopping power with the right self-defense ammo. Having something like an AR pistol or short barreled set up is also a great option because it makes it insanely easy to maneuver inside tight hallways and bedrooms if something ever happened. An AR pistol chambered in 9mm is often fairly light even with accessories like flashlights mounted onto the forend. It would be similar to having a large pistol and with the brace or stock having a second point of contact, it’s possible to use your support hand to grab items or pull your kids to safety if needed.

    When it comes to overpenetration, pistol calibers typically have decent velocity and will not go through multiple layers of drywall depending on the caliber and overall powder charge. Now I say typically because strange things happen and it’s not impossible to have a hot 9mm round not expand and punch through all types of material. I raise this point because pistol calibers have less velocity but that doesn’t always mean less penetration.

    300 Blackout and 5.56 Nato

    Home defense can be tricky with rifle calibers and it’s important to think about the benefits and possible consequences. Out of all options, 5.56 has the most velocity and muzzle energy, but once it hits drywall it will often start to tumble uncontrollably and lose energy quickly. At first, one would think 5.56 would be a terrible option for home defense because the round would overpenetrate but the 5.56’s greatest strength is also its weakness. The bullet is going so fast that it becomes extremely unstable as soon as it hits the first layer of drywall and begins to tumble. If you’re renting an apartment or house where people are closer than normal, a 5.56 might be a great option for you.

    Although longer ARs are tough to maneuver in a home defense situation they are still a viable option.

    300 Blackout is a great self-defense option in close quarters situations. people have a number of rounds to pick from when it comes to 300 Blackout. Someone can choose to use a 110gr bullet or 220gr bullet depending on the application. Typically anything over 200gr is subsonic when chambered in 300 Blackout.  When looking at home defense, it’s important to look at velocity and overall energy when deciding on your home defense round. Personally, I would not use supersonic rounds out of a 300 blackout for self-defense.

    A good friend of mine who lives in Augusta, Georgia, let his friend look at a 300 Blackout AR he built. The friend charged the rifle and didn’t see the magazine had rounds in it. He ended up pulling the trigger and the supersonic 300 Blackout round went through three interior walls along with the exterior wall of his house and his neighbor’s house. He was caught up in a fair bit of trouble with the law as a result but the even more interesting part was seeing how far the bullet penetrated. If you’re going to use 300 Blackout in a home defense role, I would seriously consider using subsonic ammunition. It will have less velocity and will be a better option for home defense especially if it’s being suppressed.

    Overall Thoughts

    When we take a step back and look at everything. I would choose either a handgun or shotgun before something like a rifle for home defense. Everyone has personal preferences and if you feel like you have to use a rifle for home defense then that’s the beauty of living in America! If I had to pick I would choose a subsonic 300 Blackout AR pistol with a shorter barrel. It packs more punch in close encounters but doesn’t overpenetrate – something like a 9mm carbine. Shot placement and knowing what’s behind your target is the most important though. At the end of the day you have to defend yourself and home with what you have but just be mindful of what’s beyond your target.

    Let me know if you would like to see a test done on interior walls with various calibers and bullet weights. I have done them in the past for product testing and would gladly test more home defense options for the sake of science. If you have certain calibers or gun types in mind let me know in the comments below. If there’s a question bouncing around in your head feel free to send me a message on my Instagram page @fridgeoperator. Stay safe out there!


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    I’m an avid shooter and love educating whether it’s at my job or in the shooting community. I’m an average joe that really loves talking with other people about firearms and other passions.
    I’m active on Instagram on @fridgeoperator.


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