If you own a .300 Blackout, you have probably come across three different weights in the ammo aisle. You have probably seen 110-, 125-, and 220-grain loads. They are all the same casing, can be used in the same magazines, but they all have completely different uses.
Some will swear that the light bullet is the best, while others feel like the 125 grain is the default go-to round, and some want the heavier bullet matched with a can so that they can stay subsonic.
TL;DR: Best .300 BLK Bullet Weight by Use Case
We get it if you don’t have time to read a whole article and you want to get your ammo now. Here are the most common uses for 300 Blackout and which grain you will need for it:
Best for Hunting & Varmints: 110 Grain. The fastest, flattest supersonic weight, so choose bonded or copper bullets for deer and hogs inside 150 yards. Shop 110 Grain .300 Blackout ammo.
Best for Training & Range Days: 125 Grain. Still supersonic with useful energy out to 250 yards, and bulk FMJ keeps high-volume practice affordable. Shop Magtech 123 Grain FMJ.
Best for Suppressed Shooting: 220 Grain. Stays under the speed of sound for a quiet shot, so pick a load built to expand if it doubles as defense ammo. Shop 220 Grain .300 Blackout ammo.
Why These Three Weights Dominate .300 Blackout
The .300 Blackout was designed to do two things in an AR-15 setup. One, to fire a fast .30 caliber bullet out of a shorter barrel. Two, easily swap to a heavier, slower bullet that can fire quietly when matched with a suppressor.
The lighter, faster end is the 110- to 125-grain bullets. These bullet weights leave a 16-inch barrel at around 2,150 to 2,375 fps and carry roughly 1,300 to 1,380 ft-lbs of energy. They cover hunting, defense, and just your general use of bullets.
The heavier end of the spectrum is 190 to 220 grains. The 220 grain is considered the classic subsonic weight firing at about 1,020 to 1,050 fps and 500 to 540 ft-lbs of energy.
These fall into the range of hot pistol cartridges instead of a rifle cartridge, but they are quiet when matched with a suppressor.
If you want to know more about the differences between subsonic and supersonic ammunition, check out our piece on Subsonic Vs Supersonic Ammo: Real Performance Differences.
110, 125 & 220 Grain Side by Side
These are typical factory numbers for each bullet weight when fired from a 16-inch barrel. Treat this table comparison as a general rule of thumb, not a promise of exact performance.
| Load | 110gr Supersonic | 125gr Supersonic | 220gr Subsonic |
|---|---|---|---|
| Muzzle Velocity | 2,350-2,375 fps | 2,185-2,225 fps | 1,020-1,050 fps |
| Muzzle Energy | 1,350-1,380 ft-lbs | 1,320-1,370 ft-lbs | 500-540 ft-lbs |
| Best Range | 0-200 yards | 0-250 yards | 0-100 yards |
| Main Use | Speed / Hunting | All-Around Supersonic | Suppressed Setups |
Weight of the bullet itself also affects drop, recoil, and impact. See our bullet weight guide How Does Bullet Weight Actually Affect Performance? to uncover more about those effects.
110 Grain .300 BLK: Speed First
The 110 grain trades bullet weight for velocity, getting the most supersonic speed from a short barrel of the three.
From a 16-inch barrel, a 110-grain bullet leaves around 2,350 to 2,375 fps. Use a 10.5-inch barrel, which is common for .300 Blackout setups, and they will still leave at about 2,200 fps.
That is the whole point of this cartridge with that size bullet. It was designed to keep the speed up when the barrel gets shorter.
Tip construction matters with the speed. A polymer-tipped varmint round is built to come apart when it hits its target. They are great on coyotes, but perform poorly on bigger animals with bigger bones.
A bonded or all-copper 110 grain is built to expand and dump more energy for better knockdown power. Same weight class, different design, different job. Our .300 Blackout ammo lineup carries 110-grain hunting loads from makers like Barnes and Hornady, though those tend to sell through fast.
The flat trajectory of this weight is the major selling point. Zeroed at 100 yards, the 110 grain will drop only about 5 to 6 inches at 200 yards. Past 250 yards and the lighter weight of the bullet starts to create more arc.
That is why the effective range of the 110 grain is better as a 0-to-200-yard hunting and defense round. This is not designed to be a long-range precision cartridge.
125 Grain .300 BLK: The All-Purpose Load
The 125 grain fits in as the most popular bullet weight for the .300 Blackout and the best all-around use.
This round is still supersonic and it carries a little more momentum than the 110 does without sacrificing much speed. This is also the weight where you will find the best training ammo for your .300 Blackout.
Factory-grade 125-grain bullets usually fire at about 2,185 to 2,225 fps from a 16-inch barrel. The energy is similar to that of the 110 grain, but it carries out past 200 yards better than the 110 due to the extra weight.
The biggest difference is how it flies, not necessarily a raw power difference.
If you are looking for more precision at longer distances, go with match-grade bullets for tighter groups. For defense ammo or hunting rounds, look for 125-grain bullets that are labeled for expansion and made for that purpose.
If you are just looking for range ammo for your .300 Blackout, there are a ton of FMJ options at 125 grain. For a bulk buy, the Magtech 123 Grain FMJ 1,000-round case sits in that same weight class and brings your cost per round down.
The effective range of the 125 grain will reach a little further than the 110, with it being effective out to 250 yards and maybe slightly beyond.
If you are looking for a good, all-around bullet weight that will be fun at the range, can take down varmints at a decent clip, and double as a home defense round, the 125 grain will fit all those uses. It isn’t quiet, but it is super practical for numerous uses.
220 Grain .300 BLK: The Quiet Heavyweight
The 220 grain is why a lot of people bought the .300 Blackout to begin with. If you keep the bullet speed under about 1,125 fps (the speed of sound) you will lose the supersonic crack sound the bullet makes.
Add on a suppressor and you get an even quieter round in a super short-barreled AR setup.
A typical 220 grain will leave the barrel around 1,020 to 1,050 fps. Put it down a 7.5- or 10.5-inch barrel and the speed barely changes, as designed.
Extra barrel length adds about 100 fps to these heavy subsonic bullets, but that can still be enough to push some past the speed of sound from a 16-inch barrel. That is not the point of these heavy loads.
Test fire a couple of mags of your specific subsonic load prior to putting faith in it. A lot of AR gas systems are tuned for supersonic pressure, and some may not cycle a 220-grain round consistently unless you have the suppressor attached.
Energy drops drastically with these heavier loads, to roughly between 500 and 540 ft-lbs. That is enough for close encounters with the right bullet.
It is not made for longer range targets. Treat the 220-grain bullet like a heavy pistol cartridge that is being fired out of an AR setup.
Expansion is the catch to these bullets. FMJ and match tips in the 220 grain will not reliably expand at such slow speeds.
If you want to use the 220 grain for hunting and defense, be sure to get 220-grain ammunition that is made to expand at these slower speeds. It is essential if you want them to be effective. Check our full .300 Blackout selection for subsonic loads with open-tip or other expanding designs.
If you need some more information on bullet expansion, check out our article on What Is Bullet Expansion? [How It Affects Stopping Power].
The effective range of the 220-grain bullet is short. A 50-yard zero is about its best range. Past that, the heavy weight and lack of speed creates a lot of drop that makes it hard to find the target at longer ranges.
For suppressed shooting under 50 yards, the 220 grain is the go-to.
If you’re wondering whether a subsonic bullet will actually open up, Ultimate Reloader shot a match hollow point and a Hornady Sub-X into gel through a suppressed AR, and the difference is pretty clear.
How Barrel Length Changes the Picture
The .300 Blackout was specifically designed and tuned for short barrels. This isn’t a marketing ploy. Advanced Armament Corp. developed it so that a compact AR could shoot .30 caliber bullets out of a 9-inch barrel while still using the standard bolt and magazines.
A 10.5-inch barrel will keep most of the speed of a 110- and 125-grain bullet compared to the 16-inch barrel.
The 220 grain velocity doesn’t change much between a 16-inch, 10.5-inch, and 7.5-inch barrel, which is why it is so popular in shorter barrel setups.
The 110 and 125 grain lose a little more of their perks if you take it down to a 7.5-inch barrel, but they perform very well out of both 10.5-inch and 16-inch barrels.
If your setup is a 9- to 10.5-inch pistol or SBR setup, the 110 grain still makes sense for both hunting and defense. The 220 grain makes more sense if you are looking for a quiet shot and/or to add a suppressor.
A 16-inch barrel is kind of the odd man out when it comes to the .300 Blackout. The cartridge was designed to get away from longer barrels without losing speed or in exchange for a quieter shot.
So if you still want some distance on your shot, you can’t go wrong with the 110- or 125-grain bullet out of a 10.5-inch barrel. You won’t lose much at all.
If you want to know more about how barrel length affects velocity and performance, check out our guide on How Barrel Length Affects Bullet Velocity and Performance.
Best .300 BLK Bullet Weight for Home Defense
For a dedicated home-defense firearm, pick an expanding bullet first and then the weight. A 110 or 125 grain built to expand will beat out the 220-grain FMJ.
A dedicated expanding 220 grain can work in a short, suppressed setup if you are comfortable with the added drop and lower energy.
Remember that .30 caliber bullets can and will keep going through drywall after a miss. These are not fast fragmenting 5.56 rounds.
That is not to discourage you from the .300 Blackout, just be sure to choose a good expanding round and know what is on the other side of your target.
Trigger-Bar Philosopher put a subsonic FMJ, a Hornady Sub-X, and a 110-grain supersonic load into gel, which shows why bullet design matters more than weight for defense.
If you are still trying to choose an AR-15 platform for home defense, check out the Top 5 Home Defense Cartridges in an AR-15 Platform article.
Best .300 BLK Bullet Weight for Hunting
Inside of 150 yards, a well-designed 110- or 125-grain hunting round can take deer and hogs, as well as be a great short-barreled varmint gun. Stick with bonded, copper, or controlled-expansion bullet designs.
You’ll want to skip a varmint tip designed bullet for anything bigger than a coyote. Don’t bother with 220-grain FMJ or match loads for hunting. A subsonic that’s been built to expand can be used on deer and hogs at closer ranges, although it’s easier with the 110 or 125 grain.
Best .300 BLK Bullet Weight for Range Days
The best bang for your buck for high-volume range days is going to be 125-grain FMJ bullets. They are the most cost effective, as they can be found in bulk, which will save you money in the long run. If a steel case doesn’t bother you, the Wolf Polyformance 145 Grain FMJ 500-round case runs a little heavier at 145 grains, is one of the most reviewed .300 Blackout loads we carry, and keeps range days cheap.
The 125 grain also has the most versatility, effective at both close and mid range, which is perfect and fun for those range days.
Now, mixing between three different bullet weights in the same rifle can drive you nuts, because each weight hits a different spot on paper. That means if you typically run a suppressor, it is best to stick with the 220-grain ammo that you will run through it. Same goes for 110 hunting rounds.
This is the exact reason most stick with the 125-grain FMJ at the range. It is a cheaper option and sits well in the middle of the three options.
If you want a good comparison of the .300 Blackout and the 5.56, check out our .300 Blackout Vs 5.56 NATO for Home Defense [Backed by Data]Â article.
So Which One Should You Buy?
Pick the 110 grain if your .300 Blackout is used for hunting or as a short-barreled varmint rifle for those flat, fast shots. Just be sure to pick the right bullet construction for the animal you are shooting, not just the weight.
Choose the 125 grain if your main focus is training, a general purpose carbine, or a good short-barreled self-defense AR setup. It is the weight that has the most utility in the .300 Blackout.
The 220 grain is your choice if noise suppression or a suppressed close-range defense setup is your main focus. Be sure that you buy good self-defense ammo that will expand at the slower speeds.
Pick the weight that fits the job you intend your .300 Blackout to do the best. Pay attention to bullet construction for that job as well. It is just as important as the weight when it comes to the .300 Blackout.
Once you make your choice, be sure to stock up on that weight ammo and head to the range. Nothing is more effective of a shot than a firearm and ammo that you are comfortable with.
Buy in bulk for the best savings possible and you won’t be sorry. Our bulk .300 Blackout ammo page is the place to start.
.300 Blackout Bullet Weight FAQs
What Is the Best All-Around .300 Blackout Bullet Weight?
For most shooters, 125 grain is the best all-around .300 Blackout choice. It stays supersonic, offers useful energy, has wide FMJ availability for training, and can work for defense or hunting when loaded with a proper expanding bullet.
Is 110 Grain .300 Blackout Better Than 125 Grain?
A 110-grain load is usually faster and flatter, making it strong for short-range hunting or varmints. A 125-grain load gives up little speed, carries momentum well, and is more versatile for training, defense, and general use.
What Is 220 Grain .300 Blackout Best For?
The 220-grain load is best for suppressed, close-range shooting. It is normally subsonic, so it avoids the sharp crack of supersonic ammo. Its lower velocity and energy make bullet expansion and realistic distance limits especially important.
How Does Barrel Length Affect .300 Blackout Bullet Weight?
.300 Blackout performs well from short barrels, especially around 9 to 10.5 inches. The 110- and 125-grain loads lose some speed as barrels shorten, while 220-grain subsonic loads change very little because they are already slow.
Which .300 Blackout Bullet Weight Is Best for Home Defense?
For home defense, choose an expanding bullet before focusing on weight. Supersonic 110- or 125-grain defensive loads are practical choices. A 220-grain subsonic can work in suppressed setups, but it needs reliable expansion at low velocity.
