You need not look far to find advice on the “perfect” ammunition to use for any given shooting discipline. Unfortunately, what works for one person or situation may be unsuitable for others. I dislike absolutists and, for some reason, a large number of them seem to hang their hats on the subject of defensive ammunition. Rather than pretending to be an authority by providing an “approved” list, I prefer to use common sense in analyzing ammo needs and then point to examples of loads that have a good chance of meeting them.
Analyzing the kind of AR-15 ammo needed for home defense requires thinking about a number of variables. We’ve covered these variables more in-depth elsewhere on Shooting Illustrated, but these concerns all boil down to the kind of defensive environment you’re working in and what limitations exist in each environment. With those limitations in mind, here are a few examples of AR-15 home-defense ammo on the market and what they can do for you:
1. Hornady Critical Defense FTX / TAP Urban
Hornady Manufacturing’s Critical Defense ammo line features reduced flash propellants, nickel-plated cases (easier to see when doing a chamber check) and flex-tip expanding bullets. These projectiles have a soft filler in the bullet’s nose that prevents an expanding cavity from filling up with thick clothing or other performance-inhibiting material. Hornady’s 55- and 73-grain FTX loads are available in .223 Rem.
I hear regular anecdotal reporting of the hunting effectiveness of Hornady’s “Gilded Metal Expanding” or GMX loads in both .223 Rem and 5.56 NATO. But since GMX bullets are designed to both expand and retain maximum weight, they may present a problem with through-shots on relatively thin, bi-pedal predators. The same is definitely true of Hornady’s TAP Urban ammunition, which has a reputation of over-penetrating soft things. Again, there are situations where such penetration may be desirable, but that is entirely dependent on your specific environment.
2. Black Hills TSX
Black Hills Ammunition offers two excellent .223 Rem. loads that incorporate Barnes’ very effective Triple Shock Expanding (TSX) bullets. The low-recoil 55-grain load is well-suited for indoor use, and the hard-hitting 62-grain load is an excellent performer, in my experience. TSX bullets are lead-free solids, made to expand and penetrate. At the high velocities commonly encountered at close range, expansion is so pronounced that they tend to stay in their intended targets much better than do other non-fragmenting bullets. Even at lower velocities—whether at long range or from short barrels—TSX bullets tend to expand well.
Remington, Barnes and Trajetech each offer .223 Rem. defensive loads using Barnes’ TSX bullets in various weights too. Cor-Bon offers similar .223 Rem. 55- and 62-grain loads in its Tipped Deep Penetrating Expanding (T-DPX) ammo line.
Federal’s Vital-Shok Nosler Partition 60-grain .223 Rem. load uses a hunting bullet that follows the same front-expander/rear-driver format. Many critters have been dropped with this bullet design, and it, too, appears to have good expansion through a variety of velocities. The company also offers 62-grain loads in its Fusion line, featuring projectiles that are purpose-built for deer. Fusion loads use low-flash propellants and have very good expansion-to-weight retention ratios, so they are worth a hard look for in-home use.
Winchester’s main contender in the same front-expander/rear-driver format is part of the PDX-1 line, in this case using a 60-grain bullet. PDX-1 projectiles feature a Split Core Technology bullet that expands in front and stays intact at the rear to drive the projectile.
5. Steel-Cased Bulk 5.56 NATO
I do not recommend going for cheap, steel-cased target fodder in home-defense loads. Sure, it may be tempting to buy that 500-round can of steel-cased, jacketed soft-point stuff for 20 cents a round. However, those loads tend to produce more flash from inefficient propellants and a lot more gas (smoke) in the room with each shot. Plus, steel cases are hard on bolt components, accelerating wear and tear. Shearing an extractor on a steel case is bad enough during range time, but it can have mortal implications when you are dealing with an intruder in a home-defense scenario.
6. M855 “Green Tip” 5.56 NATO
Surplus M855 / SS109 62-grain “green tip” ammo is widely available at very reasonable prices and is a decent back up for your primary defensive loads. At close-range velocities, these bullets tend to fracture at the cannelure into two or three main pieces. The results I have seen on bad people at close range—with correctly placed shots—are devastating. The story changes at distant ranges where M855 merely acts like a typical FMJ load, going through and through.
Incidentally, some of the 62-grain expanders, like Barnes’s TSX in the Black Hills’ loading, closely match the trajectory of 62-grain M855/SS109 ammunition. So, if you have a bunch of surplus ammo standing by for societal breakdown, switching from a primary magazine of high-quality 62-grain expanding ammo to more-affordable M855 rounds for should at least keep your zeros close.
Be sure to shoot the ammunition your firearm is chambered for. If your gun is only rated for .223 Rem. ammunition, do not shoot 5.56 NATO through it. We do not see many .223 Rem.-chambered defensive rifles produced nowadays but they are still out there. It is perfectly fine to shoot .223 Rem. ammo out of a rifle with a 5.56 NATO chamber. The hybrid chambers like .223 Wylde, .223 Fulton and the like usually can handle both cartridges’ pressure ranges, too.
When in doubt, contact the manufacturer of your firearm (or barrel) to be sure. As always, do not simply rely on your firearms and ammo to do the job of protecting you and your family. Seek professional training whenever possible and practice, practice, practice.