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Building a 300 Blackout – 4 Reasons It’s a Great AR 15 Build

Benefits of Building a 300 Blackout:

The 300 Blackout is the cool new kid on the block when it comes to AR 15s. It is based off the older 300 whisper wildcat cartridge. Building a 300 blackout is a relatively easy build to accomplish due to the fact that nearly all of standard AR 15 parts will work with 300 Blackout. The 300 Blackout is a 30 caliber projectile in a cut and necked up 5.56 caliber casing.

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1. Uses Standard AR-15 Parts

You can use a standard 80 percent lower and mill it out when building a 300 Blackout without an issue. The difference between AR 15 Kits in 300 Blackout and 5.56 is essentially just the barrel. Barrels are not the easiest part to swap on a rifle, but a shooter can swap uppers in all of three seconds. When building a 300 Blackout, you can use the same bolt and bolt carrier group as standard 5.56 AR 15s.

If you order a 300 Blackout AR 15 build kit, and have a sudden desire to shoot 5.56, all you need is a 5.56 upper and you are ready to rock and roll. Standard 5.56 magazines will work with the 300 Blackout without issue, or even a loss of a round or two. The simple fact is, nearly every standard AR 15 part will work with 300 Blackout and that is the reason building  300 blackout is growing in popularity.

2. Power Factor

The 5.56 uses a 22 caliber projectile, which is noticeably smaller than the 30 caliber projectile the 300 Blackout uses. This means that the 300 Blackout can be considerably heavier than the 5.56 and does significantly more damage.

The lightest 300 Blackout load is much heavier than the heaviest 5.56 load. The 110 grain 300 Blackout load retains a supersonic nature and hits harder at ranges inside 500 yards. It delivers greater foot pounds of energy on a target, and because of its larger size, creates a larger wound cavity.

Overall, it’s a superior round to the 5.56 in everything but longer-range performance. This is why the two make a good pair. They both do different jobs and complement each other well.

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3. Uses of the 300 Blackout

300 Blackout (8.5" Barrel & 7" Keymod Handguard) AR Pistol Upper

The idea of building a 300 Blackout for hunting is becoming increasingly popular. Since the AR 15 is an accurate, reliable, ergonomic and easy shooting rifle, it is not hard to see why. Unfortunately, many states require a projectile to be over .22 in diameter. This immediately rules out 5.56/223.

The 30 caliber 300 Blackout is not only perfectly legal, but a better all-around hunting round. Ethically, most hunters will not take a shot past 300 yards in fear of merely wounding the animal and causing suffering. Inside 300 yards the 300 Blackout rules. What’s important to remember is that the 300 Blackout is not as powerful as the 308 or 30-06. It shouldn’t be used for large game, but for medium-sized game and predators like deer and hogs.

The round is fully capable of taking any American Whitetail deer without issue. The combination of the 300 Blackout and AR 15 platform makes this a hog-bustin round. Hogs are invasive species and commonly travel in packs. With a semi auto rifle you can engage multiple targets in short succession.

4. Home Defense

Burglar entering through a window

The 300 Blackout is also an excellent self-defense round. Again, it is bigger and creates a larger wound cavity. It also functions well out of a short barrel, like an AR pistol. The heaviest 300 Blackout rounds are subs2onic and at close range can be devastating. Mixed with a suppressor, you have a home defense platform that won’t blow your eardrums out.

The 300 Blackout is an excellent option for your first 80 lower build, or you can buy a complete AR 15 build kit in 300 Blackout. If you already have a rifle and are interested in a conversion, check out our .300 Blackout Upper Assembly!

300 Blackout (16" Barrel & Keymod Handguard) AR 15 Rifle Upper Assembly

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