$227.50–$1,820.00Price range: $227.50 through $1,820.00
Atomic Ammunition .300 Win Mag 175gr HP BT subsonic ammo harnesses the magnum case capacity for maximum subsonic energy in a suppressor-optimized long-range platform.
Shop 300 Win Mag subsonic ammo from Atomic Ammunition. Our 175gr HP BT subsonic brings hearing-safe suppressed shooting to the .300 Winchester Magnum platform — one of the most versatile long-range calibers in existence. Run subsonic for quiet training and noise-sensitive applications, then swap to full-power loads for long-range work. No rifle changes needed — just swap your magazine and re-zero.
The .300 Win Mag’s oversized case capacity provides a unique advantage in subsonic loading: more consistent powder burn characteristics at low velocities and the flexibility to run both subsonic and full-power supersonic loads through the same rifle. At 1,050 fps with a suppressor, the .300 Win Mag becomes dramatically quiet — 35–45 dB of noise reduction brings it below hearing-damage thresholds. The 175gr HP BT delivers match-grade accuracy at subsonic velocities, and the 428 ft-lbs of energy is effective for close-range hunting applications where stealth is critical.
American-Made Components & Quality
Every cartridge is loaded with American-made components: new brass cases, precision-weighed Hodgdon powder charges, and match-grade 175gr HP BT projectiles. Hand-inspected for performance consistency. Atomic Ammunition — 100% American-made.
Frequently Asked Questions
Will this cycle my semi-auto .300 Win Mag?
Subsonic magnum loads are designed for bolt-action rifles. Semi-auto cycling is not guaranteed at subsonic velocities.
Can I use the same rifle for supersonic and subsonic?
Yes. Simply switch ammunition and re-zero. No barrel or action changes needed. This is one of the key advantages of subsonic .300 Win Mag.
How does the energy compare to .308 subsonic?
Both the .300 Win Mag and .308 Win deliver approximately 428 ft-lbs at subsonic velocities with a 175gr bullet. The magnum’s advantage is in supersonic versatility, not subsonic energy.
Is the brass reloadable?
Yes. New boxer-primed brass, fully reloadable.
What is the minimum order?
Minimum order is 100 rounds. Bulk discounts on 200+ rounds.
