300 Blackout vs 223 Ballistics & Uses – In-Depth Review

The .223 Remington, a cartridge that was adopted as the 5.56×45 mm and has been serving the U.S Military and NATO forces for more than four decades now. It also has the honor of being one of the most popular civilian cartridges in the United States, the primary chambering for the venerable AR-15. On the other end of this balance scale, we have the .300 Blackout, a cartridge that was designed to substitute the .223 Remington with a simple swap of the barrel. 

These cartridges differ but also allow you to quickly convert an AR-15 from a .22 caliber to a .30 caliber rifle. Scour through this guide to learn if that change is worth it and if you should prefer one over the other. 

TL;DR: 300 Blackout vs 223

Here’s a quick overview of the comparison, if you don’t have the time to read the entire guide.

300 Blackout Overview

The .300 AAC Blackout, also known as the .300 blk is an intermediate rifle cartridge designed in the United States for use with the M4 platform. It is a 7.62×35 mm cartridge that was developed to imitate the ballistics of a 7.62×39 mm (AK-47 round) inside an M4 carbine. Interestingly, the round was made to be compatible with the 5.56 NATO chambered M4 rifles by using the same magazines (without compromising on capacity) and all other parts except for the barrel. 

This means that a 5.56 NATO chambered M4 rifle can be instantly converted into a .30 caliber rifle with a simple swap of a barrel or the BCG. This round was developed by Advanced Armament Corporation in cooperation with Remington Defense in 2009 and approved by SAAMI in 2011. 

The lead developers later unveiled that the round was developed for the requirements of the military to deliver the power of a .30 cal bullet in their existing M4 rifles. Especially for the special forces units. There were other options already available for this, but lacked interoperability with the M4 platform and had feeding issues. Although the military did never adopt the .300 blk in a widespread capacity, this round is quite popular among the civilian AR-15 user community. 

223 Overview

The .223 Remington (or .223 Rem or .223) is a rimless bottlenecked rifle cartridge developed in 1962 after a collaboration between Remington Arms and Fairchild Industries. The goal was to develop a smaller caliber, high-velocity round for the United States Army, and the project was overseen by the U.S CONRAC (Continental Army Command). 

The development started in 1957 and after many years of to-and-fro, the final result was out in 1962. In 1963, Remington introduced the first rifle chambered for this newly developed cartridge, the Model 760. 

For those who don’t know, the .223 Remington is the parent cartridge of the 5.56×45 mm NATO cartridges which are used by the military. In fact, the development of the .223 Rem was intended for the military, and it was rightfully adopted in the 1980s. 

Many people consider the .223 Remington to be the same as the 5.56 NATO. However, these rounds may look the same on the outside, they differ in chamber pressure, throat length of the cartridge, chamber dimensions, and case wall thickness. 

The .223 Rem is the main chambering for the insanely popular AR-15 rifle and is one of the widely used cartridges of the world. 

300 Blackout vs 223: Cartridge Specs

Here’s a table outlining the dimensions of these cartridges:

	300 Blackout	223
Bullet Diameter	0.308 in (7.8 mm)	0.224 in (5.7 mm)
Neck Diameter	0.334 in (8.5 mm)	0.253 in (6.4 mm)
Base Diameter	0.376 in (9.6 mm)	0.376 in (9.6 mm)
Case Length	1.368 in (34.7 mm)	1.76 in (45 mm)
Overall Length	2.26 in (57 mm)	2.26 in (57 mm)
Case Capacity	21 grains	28.8 grains
Max Pressure (SAAMI)	55,000 psi	55,000 psi
Typical Casing Material	Brass	Brass
Typical Bullet Weight (gr)	110-150 grains	55-78 grains

The .300 blk has been mainly derived from the .300 Whisper concept but is more like a mix of a .30 cal and a .22 cal bullet. Since it was designed to be used interchangeably with the .223/5.56, the major dimensions such as the base diameter, OAL, and chamber pressure are the same. 

This allows both these cartridges to use the same BCG and also the same magazines without compromise on capacity. The major areas where these cartridges differ are the bullet diameter, case length, and neck diameter. Since the .300 blk uses a .30 cal bullet and the .223 Rem uses a .22 cal bullet, these differences are obvious and necessary. 

The .300 blk features a 30% lesser case capacity compared to the .223 and uses almost twice as heavy bullets. The best twist rate for a .300 blk is 1 in 8 inches, and the cartridge can achieve its terminal potential with a 9-inch barrel. On the other hand, the .223 Rem commonly uses a 1 in 12 inches twist rate (faster for longer and heavier bullets) and works great with a 16, 20, and 24-inch barrel. 

300 Blackout vs 223: Ballistics

The best method to estimate the effective range and accuracy of a round is to understand its ballistics. This includes the trajectory, velocity and energy data over a specific distance which helps us understand the performance of different variations of a round, and average out the expected outcome. 

300 Blackout vs 223: Trajectory

The trajectory for these rounds has been compared out to 1,000 yards, and using the most common bullets and barrel lengths. 

300 blk

16” barrel/BC 0.290/110 gr Hornady V-Max	9” barrel/BC 0.251/120 gr Copper HP	16” barrel/BC 0.406/150 gr FMJ Boat-Tail
100 yds: 0 “ Drop	100 yds: 0 “ Drop	100 yds: 0 “ Drop
200 yds: 6.5 “ Drop	200 yds: 9.4 “ Drop	200 yds: 10.3 “ Drop
300 yds: 23.4 “ Drop	300 yds: 33.7 “ Drop	300 yds: 34.7 “ Drop
400 yds: 54 “ Drop	400 yds: 78.6 “ Drop	400 yds: 76.9 “ Drop
500 yds: 102.7 “ Drop	500 yds: 150.6 “ Drop	500 yds: 140.2 “ Drop
1,000 yds: 806.3 “ Drop	1,000 yds: 1075.6 “ Drop	1,000 yds: 902.9 “ Drop

.223 Rem

24” barrel/BC 0.269/55 gr FMJ	24“ barrel/BC 0.255/62 gr Trophy Bonded Tip	24” barrel/BC 0.372/77 gr Sierra Matchking BTHP
100 yds: 0 “ Drop	100 yds: 0 “ Drop	100 yds: 0 “ Drop
200 yds: 2.7 “ Drop	200 yds: 3.3 “ Drop	200 yds: 4.2 “ Drop
300 yds: 10.9 “ Drop	300 yds: 13.1 “ Drop	300 yds: 15.2 “ Drop
400 yds: 26.1 “ Drop	400 yds: 31.5 “ Drop	400 yds: 34.4 “ Drop
500 yds: 51.1 “ Drop	500 yds: 61.7 “ Drop	500 yds: 64.5 “ Drop
1,000 yds: 474.1 “ Drop	1,000 yds: 573.1 “ Drop	1,000 yds: 483 “ Drop

The trajectory data recorded out to 1,000 yards shows us some interesting but expected findings. The .300 blk being a bulky .30 caliber round and with a short case loaded with less powder, starts dropping horrifically after 300 yards. The drop ranges from 23 to 34 inches at 300 yards for the lightest and heaviest bullets in our data. 

The data does not amaze me at all, because the .300 blk was only designed to achieve the ballistics of a 7.62×39 mm and which it has done perfectly. This cartridge was designed for short and medium range hard-hitting uses, and it fares quite well on accuracy within that range. 

Turning towards the .223 Rem, the lightweight bullet showed an amazing trajectory out to 400 yards, and an acceptable drop out to 500 yards. A trained shooter can use adjustments to accurately hit targets out to 800 yards with the right scope and skills. In fact, the 1,000 yard drop for this round does not seem bad at all, when we look at the size of the cartridge and the recoil. 

Comparing these two cartridges for accuracy, the .223 Rem is a clear winner at all ranges. Whereas, the .300 blk is a good performer if you keep the distance within 300 yards. 

300 Blackout vs 223: Velocity & Kinetic Energy

The velocity and kinetic energy data will help us determine the maximum effective range and the suitability of targets at short, medium and long range.

300 blk

16” barrel/BC 0.290/110 gr Hornady V-Max	9” barrel/BC 0.251/120 gr Copper HP	16” barrel/BC 0.406/150 gr FMJ Boat-Tail
150 yds: 1,961 ft/s, 940 ft.lbs	150 yds: 1,799 ft/s, 863 ft.lbs	150 yds: 1,724 ft/s, 990 ft.lbs
200 yds: 1,834 ft/s, 821 ft.lbs	200 yds: 1,533 ft/s, 626 ft.lbs	200 yds: 1,561 ft/s, 811 ft.lb
300 yds: 1,597 ft/s, 623 ft.lbs	300 yds: 1,307 ft/s, 455 ft.lbs	300 yds: 1,411 ft/s, 663 ft.lbs
400 yds: 1,389 ft/s, 471 ft.lbs	400 yds: 1,136 ft/s, 344 ft.lbs	400 yds: 1,282 ft/s, 547 ft.lbs
500 yds: 1,218 ft/s, 362 ft.lbs	500 yds: 1,024 ft/s, 279 ft.lbs	500 yds: 1,174 ft/s, 459 ft.lbs
1,000 yds: 846 ft/s, 175 ft.lbs	1,000 yds: 752 ft/s, 151 ft.lbs	1,000 yds: 897 ft/s, 268 ft.lbs

.223 Rem

24” barrel/BC 0.269/55 gr FMJ	24“ barrel/BC 0.255/62 gr Trophy Bonded Tip	24” barrel/BC 0.372/77 gr Sierra Matchking BTHP
100 yds: 2,874 ft/s, 1008 ft.lbs	100 yds: 2,680 ft/s, 989 ft.lbs	100 yds: 2,481 ft/s, 1,053 ft.lbs
200 yds: 2,536 ft/s, 785 ft.lbs	200 yds: 2,339 ft/s, 753 ft.lbs	200 yds: 2,255 ft/s, 869 ft.lbs
300 yds: 2,222 ft/s, 603 ft.lbs	300 yds: 2,024 ft/s, 564 ft.lbs	300 yds: 2,041 ft/s, 712 ft.lbs
400 yds: 1,389 ft/s, 471 ft.lbs	400 yds: 1,736 ft/s, 415 ft.lbs	400 yds: 1,838 ft/s, 478 ft.lbs
500 yds: 1,218 ft/s, 362 ft.lbs	500 yds: 1,480 ft/s, 302 ft.lbs	500 yds: 1,652 ft/s, 466 ft.lbs
1,000 yds: 846 ft/s, 175 ft.lbs	1,000 yds: 880 ft/s, 107 ft.lbs	1,000 yds: 1,032 ft/s, 182 ft.lbs

The .300 blk is a supersonic cartridge out to 600 yards in most cases, when fired from an appropriate barrel length. In fact, the .300 blk is quite popular for its subsonic loads which work great with suppressors and SBR (Short Barrel Rifle). Pertaining to its size and capacity, the .300 blk is a great cartridge for short to medium range. 

The .223 Rem is an exceptionally supersonic cartridge that can achieve muzzle velocities as high as 3,200 fps. That is almost three times the supersonic threshold. However, this supersonic capability of the .223 Rem is short-lived because of the lightweight bullets. The incredibly fast speeds do offer accuracy out to a significant range (even out to 1,000 yards with 77 gr loads), but also remember that they eat up the barrel pretty fast. That’s why most AR and M4 barrels are chrome-lined. 

Looking at the energy data, I always take the benchmark as 1,000 foot-pounds of energy, which is the widely accepted and legal minimum energy required to hunt a deer in all states. The .300 blk does have that kind of energy, but only within 120 yards. Whereas the .223 Rem mostly lacks that much energy but sometimes can touch that 1,000 fpe within 100 yards. 

Either way, both these cartridges were designed for combat, and have a significant amount of energy at medium range. As a matter of fact, 100 fpe is enough to handle small game and even humans. 

300 Blackout vs 223: Stopping Power

The stopping power of a bullet is the indicator of, well… the power to incapacitate or kill a target as quickly as possible. In other words, it describes how deadly a bullet is, and if it will be suitable for medium game, big game, combatants, armor, or anything else. 

300 blk

16” barrel/BC 0.290/110 gr Hornady V-Max Sectional Density: 0.166	9” barrel/BC 0.251/120 gr Copper HP Sectional Density: 0.181	16” barrel/BC 0.406/150 gr FMJ Boat-Tail Sectional Density: 0.226
100 yds: 32 lb.ft-s	100 yds: 30 lb.ft-s	100 yds: 36 lb.ft-s
200 yds: 28 lb.ft-s	200 yds: 26 lb.ft-s	200 yds: 33 lb.ft-s
300 yds: 25 lb.ft-s	300 yds: 22 lb.ft-s	300 yds: 30 lb.ft-s
400 yds: 21 lb.ft-s	400 yds: 19 lb.ft-s	400 yds: 27 lb.ft-s
500 yds: 19 lb.ft-s	500 yds: 17 lb.ft-s	500 yds:  25 lb.ft-s
1,000 yds: 13 ft.lb-s	1,000 yds: 11 ft.lb-s	1,000 yds: 14 ft.lb-s

.223 Rem

24” barrel/BC 0.269/55 gr FMJ Sectional Density: 0.157	24“ barrel/BC 0.255/62 gr Trophy Bonded Tip Sectional Density: 0.177	24” barrel/BC 0.372/77 gr Sierra Matchking BTHP Sectional Density: 0.219
100 yds: 22 lb.ft-s	100 yds: 23 lb.ft-s	100 yds: 27 lb.ft-s
200 yds: 19 lb.ft-s	200 yds: 20 lb.ft-s	200 yds: 24 lb.ft-s
300 yds: 17 lb.ft-s	300 yds: 17 lb.ft-s	300 yds: 22 lb.ft-s
400 yds: 10 lb.ft-s	400 yds: 15 lb.ft-s	400 yds: 20 lb.ft-s
500 yds: 9 lb.ft-s	500 yds: 13 lb.ft-s	500 yds: 18 lb.ft-s
1,000 yds: 6 ft.lb-s	1,000 yds: 7 ft.lb-s	1,000 yds: 11 ft.lb-s

The two most definitive factors to decide the stopping power of a round are the sectional density (SD) and momentum. The SD is the ratio of the weight and cross-sectional area of the bullet, and it defines the level of penetration that can be achieved. Another factor is the momentum, which is the measure of the efficacy of energy transfer from the moving bullet to the target. 

Upon collectively analyzing these two factors, we get an idea of the depth of penetration, size of the wound cavity, and the level of tissue damage. In simpler terms, the higher the value of momentum, the more damage will be done by the bullet. 

An SD is greater than .230 and up to 0.260 is considered suitable for hunting deer-sized game. Anything less is for small game, and anything more is good for bigger game animals. The .300 blk is clearly not a deer hunting round with its maximum SD reaching only 0.226. However, looking at the data for momentum, it can have a good amount of stopping power out to 400 yards. 

The .223 Rem is clearly not a deeply penetrating round, even with the heaviest bullet weights. The momentum isn’t too much, and it also falls behind when compared with the .300 blk cartridge. 

300 Blackout vs 223: Use Cases & Effective Range

Coming to the important part, let us now analyze the best uses and effective range for these cartridges. 

Small Game Hunting / Varminting

The .223 Rem is an incredibly useful small game cartridge and is widely used for varminting purposes. The .22 caliber bullet and the centerfire case make it a very popular option, and the low recoil along with the optimal stopping power and a lightweight rifle makes it perfect for small game. On the other hand, the .300 blk is an overkill for small game animals in most cases. The .30 cal bullet is quite big and powerful, and also unnecessary for small game.

Deer or Medium Size Game Hunting

The .300 blk won’t be appropriate to hunt a deer because of the short effective range, and you cannot do that legally in most states and also humanely with the .223 Rem. There are many better ammo options for hunting deer, which can also prove to be quite versatile. However, when medium size game is concerned, the .300 blk is a perfect hog-medicine, and also a viable defense gun out in the woods. 

Long Range Uses

Looking at the trajectory and velocity data, and also from experience, neither of these rounds is optimal for long range engagements. However, I will still like to point out that although the .300 blk does not stand a chance at long range, the .223 Rem does have some potential for 600-700 yard shots in the right hands. 

Competitions

The .223 Rem is widely used in 3-gun competitions with the AR-15 and has proven effective a lot of times. Additionally, the .300 blk is also a popular 3-gun competition cartridge, mainly preferred due to its SBR compatibility and controllability. 

Tactical Applications and Home Defense

It is a fact that both these cartridges were designed for tactical and combat applications. The .223 Rem has proven its effectiveness on the battlefield in the form of the 5.56 NATO. Whereas, the .300 blk is also in use with some military special forces, and is great for CQB engagements. 

As far as home defense is concerned, I will recommend you evaluate the possible overpenetration issues with ply boards and MDF. The .223 Rem has been considered a suitable home defense round in an AR-15 and is a better pick over the bigger .30 cal .300 blk rounds. However, make sure to pick the right ammo for that. 

300 Blackout vs 223: Costs, Availability, & Compatibility

Before you pick any cartridge, it is important to understand the availability and possibilities related to it. 

Cheap and Abundant

The .223 Rem has been around for quite some time, and it is among the most easily available and abundant ammo options in the country. These rounds can be found for as low as $0.5 to only as high as $1.5 per round. Due to the popularity of the AR-15 platform, every online and offline ammo gun stacks it up in good amounts. However, during the Covid-19 pandemic buying, this ammo went scarce and pricey for some time. So consider having some backup ammo or reloading supplies. 

The .300 blk has also gained popularity in recent years, and ammo can be found at $1 to $3 per round. The availability is good, but not as extensive as the .223 Rem, so keep an eye out for that. 

Tons of Options and Customizability 

The .223 Rem and .300 Blk are most widely used in the AR-15 platform, which is undoubtedly the most popular, and customizable weapon platform in the civilian market. There are a lot of options for rifles, mostly semi-auto, and only a few bolt actions. As far as ammo is concerned, the .223 Rem has a wider number of options than the .300 blk because of being a mainstream cartridge. 

Bottom Line

The .223 Rem was designed to be used in combat, and its derivative, the 5.56 NATO is an accomplished and widely used military cartridge. Although it fires a small .22 caliber bullet, the .223 Rem delivers supersonic speeds and an amazing accuracy out to 500 yards, with a potential of being used to 1,000 yards. 

The .300 blk was designed to quickly switch from the 5.56 NATO cartridge to its .30 caliber round in an M4 rifle platform. It is the equivalent of the Russian 7.62×39 mm cartridge and quickly interchanges with a 5.56/.223 platform with the need to only change the barrel. It is a good short and close range cartridge, with exceptional subsonic capabilities, and is also great for use with suppressors and SBR. Although, it is not a great hunting cartridge because of the short effective range.