Sellier & Bellot 300 Blackout 124gr FMJ — 20 Round Box

Description

Sellier & Bellot 300 Blackout 124gr FMJ — 20 Round Box

The Sellier & Bellot 300 Blackout 124gr FMJ delivers the brass-cased, Boxer-primed training ammo your suppressor-ready AR platform deserves — without the premium pricing of specialty loads.

Sellier & Bellot has manufactured ammunition since 1825, and that history shows in how they build this load. The 124-grain FMJ bullet features a CuZn10 copper-zinc jacket over a standard lead core, producing a 0.308-inch diameter projectile with a G1 ballistic coefficient of 0.379 — consistent performance round to round at the range. Because the cases are new brass and Boxer primed, reloaders get clean, reloadable brass after every session, which makes this one of the better-value training options for high-volume 300 BLK shooters.

Muzzle velocity runs 2,165 fps with 1,291 ft-lbs of energy, putting this squarely in supersonic territory. As a result, this load cycles reliably in standard-rate AR-platform rifles and functions as a solid zero-confirmation and training complement to any subsonic or expanding carry load you run alongside it.

Key Features — Sellier & Bellot 300 Blackout 124gr FMJ

• Caliber: 300 AAC Blackout
• Bullet Weight: 124 grains
• Bullet Type: Full Metal Jacket (FMJ)
• Jacket Material: CuZn10 (copper-zinc)
• Bullet Diameter: 0.308″
• Muzzle Velocity: 2,165 fps
• Muzzle Energy: 1,291 ft-lbs
• Ballistic Coefficient: G1 0.379 / G7 0.191
• Case: New brass, Boxer-primed, reloadable
• Rounds Per Box: 20
• SKU: SB300BLKA

Why This Product Stands Out — Sellier & Bellot 300 Blackout 124gr FMJ

300 Blackout training ammo is expensive relative to 5.56, so the brass-to-cost ratio matters. Specifically, S&B uses new brass and Boxer primers on every round, meaning you’re not burning money on steel-cased ammo you can’t reload. For the competitor or volume shooter running a dedicated 300 BLK upper, that reloadability lowers your long-term cost per round substantially.

Furthermore, this is a supersonic load calibrated to run reliably through standard-rate-of-twist barrels without needing a suppressor or any special bolt timing. Because it hits 2,165 fps at the muzzle, it functions identically to the platform’s full cycling profile — which makes it the right load for zeroing and building fundamentals before switching to subsonic or hunting loads at the range.

S&B is part of the Colt CZ Group and produces ammunition under strict European quality controls. As a result, lot-to-lot consistency is strong — important when you’re confirming a zero or validating your rifle’s function before a hunt or competition stage.

Ideal Use Cases

• Range training and volume target shooting
• Zero confirmation for 300 BLK builds
• Function testing for suppressor-host rifles prior to switching to subsonic loads
• Brass collection for 300 BLK reloaders

Technical Specifications

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Manufacturer: Sellier & Bellot

Model: 300 AAC Blackout FMJ Training

Type: Centerfire Rifle Ammunition

Caliber: 300 AAC Blackout

UPC: 754908512447

SKU: SB300BLKA