Not sure the best ammo to feed your AR for the range and home defense?
We’ll go over caliber, barrel twist, bullet type, and price range to find your perfect fit.
Ready to begin?
AR-15 Calibers: 5.56 vs .223
Your average AR-15 comes in two popular calibers, the 5.56x45mm NATO and the .223 Remington.
You can double-check what it is by looking at your model specs or physically on your barrel, which should be stamped with the caliber and barrel twist rate.
The two cartridges are physically identical but the 5.56 may be loaded to higher pressures than .223 ammunition.
The .223 is a civilian round and has SAAMI specs (organization that sets standards for pressure and dimensions) while the 5.56 is a military round that has their own specifications that might require higher pressure for higher velocity.
Therefore, it’s best to follow the advice:
- 5.56 chamber: OK to fire both 5.56 and .223
- .223 chamber: OK to fire only .223
Your barrel or rifle probably won’t instantly blow up from shooting a 5.56 in a .223, but why risk it?
Combine that with the variance in the machining of the barrel and ammo production standards, it’s best to use the proper ammunition.
AR-15 Barrel Twist
Your barrel stamp should indicate the barrel twist after the caliber.
You should see a ratio from 1:7 all the way up to 1:12 and it means that the barrel will spin the bullet one revolution every X inches. Most barrels will be from 1:7 to 1:9 twist, with the most popular being 1:9.
Take a look at the chart below to see the ideal twist rate for your barrel.
The heaver grain bullets are usually reserved for the military and their tracer rounds.
With normal cartridges, you’re most likely to see 55 grain and 62 grain bullets. These are fine to shoot in 1:7 to 1:9 barrels and you probably won’t even notice a difference up to 300 yards.
You’ll see two big families of bullet types, the full metal jackets (FMJ) and the hollowpoint/softpoints (HP/SP).
The FMJ’s are great for plinking while HP/SP are more for home defense or long range applications.
Other confusing acronyms you might see include (BT) which means boat-tail and indicate the back of the bullet has a more aerodynamic shape than simply cutting off straight. The middle one below is a FMJ-BT.
Lastly, if you’re looking at military 5.56 rounds, you’ll see M193 and M855. The 55 grain M193 is the standard FMJ (sometimes referred to as “ball” ammo) of the military while the 62 grain M855 is the “green tip” penetrator round that has a steel rod inside (light gray).
Things to keep in mind for 193 vs 855:
- Pricing is similar
- M855 is better at penetration (duh?)
- Some ranges do not allow steel core ammo
- M193 is better at soft targets under 100 yards
- More info about the differences
Range Plinking AR-15 Ammo Recommendations
Finally, the recommendations! We recommend buying from Lucky Gunner because:
- We’ve been customers for over 6 years
- Active stock management so you don’t end up getting a back-order email days later
- Easy to figure out shipping costs without registering
- 110% guarantee your order will ship the next day
Best AR-15 5.56 Ball Ammo
Now we combine the good stuff we learned above and stick to 55/62 grain bullets that are close to military specifications. These are the rounds that we’ve shot tons of and never had a problem.
Our suggestions are also all brass cased so you can keep them if you think you might ever start to reload your own ammo in the future.
- PMC X-TAC – Assorted – 55 gr M193 (Best price/availability if you want to get near mil-spec)
- Federal Gold Match – 20 Rounds – 69 gr (More accurate/heavier rounds for precision shooting)
Best AR-15 Green Tip 5.56 Ammo
- PMC X-TAC – Assorted – 62 gr M855 (Good price and almost always in stock…get your penetrators!)
Best AR-15 .223 Ammo
If your barrel is .223 or if you want to shoot some slightly lighter loads in your 5.56 barrel.
- PMC Bronze – 20 Rounds – 55 gr FMJBT (Best .223 option)
Best .223 Plinking Ammo
We don’t readily use these next suggestions in our AR’s, but if you’re really trying to save money, you can opt for Russian steel or coated steel cartridges.
Start off with a small batch first since some AR-15’s don’t like steel cased ammo. They offer pretty good savings but are dirtier shooting and less accurate…but probably great for the range.
Also keep in mind that you can’t save these to reload later, and you need to shoot at a range that allows both steel casings and bi-metal bullets.
Self-Defense AR-15 Ammo
For self-defense you want the bullet to put all its energy into the bad guy by breaking apart.
That means FMJ and the penetrator rounds are usually not the best choice. I recommend going with specific use self-defense ammo that are hollow point and yet still have a plastic ballistic tip that helps stability.
So there you have it, our recommendations for the best AR-15 ammo in both .223 and 5.56.
Let us know what you went with and how it runs in your AR.