Magtech 300 Blackout 123gr FMJ – Great Supersonic Range Ammo 50 Rounds

Description

Magtech 300 Blackout 123gr FMJ is the supersonic side of the cartridge, loaded by CBC in Brazil and packed 50 to the box rather than the 20 that most 300 Blackout ships in. That packaging difference is the whole appeal, because 300 BLK practice ammunition is normally punishingly expensive.

• Where Magtech 300 Blackout 123gr FMJ sits in the cartridge
• Full specifications
• Why buy Magtech 300 Blackout 123gr FMJ in bulk
• Honest notes before you buy
• The one serious warning about Magtech 300 Blackout 123gr FMJ
• The bottom line

Where Magtech 300 Blackout 123gr FMJ sits in the cartridge

The 300 Blackout has two distinct personalities. Subsonic loads run 190 to 220 grains at around 1,000 feet per second for suppressed use. Supersonic loads like Magtech 300 Blackout 123gr FMJ push a lighter bullet to roughly 2,230 feet per second, which is where the cartridge behaves like a short barrelled 7.62×39 rather than a quiet specialist.

The 123 grain weight is the most common supersonic loading and is what most 300 BLK rifles with 1:7 or 1:8 barrels are set up for. It cycles reliably in unsuppressed carbines without any gas adjustment.

Full specifications

• Caliber: 300 AAC Blackout
• Bullet weight: 123 grain
• Bullet: Full Metal Jacket
• Velocity: approx 2,230 fps, supersonic
• Case: Brass, boxer primed, reloadable
• Primer: Non corrosive
• Rounds per box: 50
• Rounds per case: 1000
• Warning: Will chamber in 5.56 barrels, store separately

Brass cased and boxer primed with non corrosive primers. The bullet is a conventional copper jacketed lead core full metal jacket, which feeds cleanly from standard AR magazines loaded for 300 Blackout.

Why buy Magtech 300 Blackout 123gr FMJ in bulk

Cost per round is the entire argument. Magtech 300 Blackout 123gr FMJ at 50 rounds per box and 1000 per case brings the price down to somewhere a person can actually practise, which has historically been the reason 300 BLK rifles sit in safes rather than getting shot.

It is also brass and reloadable, which matters more in this cartridge than most. Many 300 Blackout shooters form their own cases from .223 brass, and clean once fired 300 BLK brass saves that step entirely.

Honest notes before you buy

Never store 300 Blackout and 5.56 ammunition in the same container or range bag compartment. A 300 Blackout round will chamber in a 5.56 barrel and firing it destroys the rifle, often injuring the shooter. This is the single most common catastrophic mistake with the cartridge and it happens to experienced people.

Colour code or physically separate your magazines too. Mark 300 BLK magazines distinctly, and never load a mixed bag at a range where you are also shooting an AR-15 in 5.56.

The one serious warning about Magtech 300 Blackout 123gr FMJ

This is the important caveat. Magtech 300 Blackout 123gr FMJ is practice ammunition. The full metal jacket bullet does not expand, which rules it out for defense and for hunting, and FMJ is illegal for deer in many states. Buy an expanding supersonic load for hunting and a proper defensive load for defense.

Stored dry it keeps for decades. Keep it clearly labelled and separated from 5.56, which is a storage discipline worth more than any other advice on this page.

The bottom line

Barrel length matters for velocity. Supersonic 300 Blackout was designed around a 9 to 16 inch barrel and gains little beyond that, so a 16 inch carbine gives you essentially full performance. You can read more about the bullet design at swiftbullets.com, or browse the rest of our stock on the MAG5 Firearms ammunition page.

MAG5 Firearms keeps the Magtech 300 Blackout 123gr FMJ in stock and moving, and we are glad to talk through bullet choice before you order. If you are working up a load for a new rifle, a single box of the Magtech 300 Blackout 123gr FMJ is a sensible place to start.