$170.00–$1,360.00Price range: $170.00 through $1,360.00
Atomic Ammunition .300 Blackout 220gr HP BT cycling subsonic ammo is built to reliably cycle suppressed AR-15s — the gold standard for quiet semi-auto shooting.
Caliber: .300 AAC Blackout
Bullet: 220gr Hollow Point Boat Tail
Velocity: 1,050 fps — subsonic, eliminates sonic crack
Energy: 538 ft-lbs at muzzle
Cycling: Reliable semi-auto function in suppressed AR-15s
.300 Blackout 220gr HP BT Cycling Subsonic Ammunition
Buy 300 Blackout subsonic ammo from Atomic Ammunition. The .300 Blackout was designed from the ground up for suppressed AR-15 shooting, and our 220gr HP BT cycling subsonic load delivers on that promise: reliable semi-auto cycling, hearing-safe noise levels, and 538 ft-lbs of energy downrange. This is 300 Blackout suppressor ammo done right — match-grade consistency in every round.
Performance Specifications
Specification
Details
Caliber
.300 AAC Blackout
Bullet Weight
220 grains
Bullet Type
Hollow Point Boat Tail (HP BT)
Muzzle Velocity
1,050 fps (subsonic)
Muzzle Energy
538 ft-lbs
Sound Reduction
30–40 dB with suppressor
Cycling
Reliable in standard AR-15 gas systems
Casing
New brass — boxer-primed, reloadable
Application
Suppressed AR-15, home defense, tactical
Suppressed Cycling Performance
The .300 Blackout is the king of suppressed semi-auto shooting, and the 220gr subsonic is its signature load. Atomic’s cycling subsonic reliably feeds, fires, and ejects in standard AR-15 gas systems without the need for adjustable gas blocks. With a suppressor, noise drops below 125 dB — dramatically quieter than unsuppressed supersonic fire. The 538 ft-lbs of energy at the muzzle makes this an effective close-range option for home defense, and the match-grade HP BT delivers consistent accuracy at distances where subsonic shooting excels (inside 200 yards).
American-Made Components & Quality
Every round is loaded with American-made components: new brass cases (reloadable), precision-weighed Hodgdon powder charges, and match-grade 220gr HP BT projectiles. Hand-inspected for the cycling reliability that suppressed AR-15 shooters depend on. 100% American-made ammunition — no imported components.
Frequently Asked Questions
Will this cycle my AR-15 in .300 BLK?
Yes. Our cycling subsonic is specifically tuned for reliable semi-auto function in standard .300 Blackout AR-15 gas systems. Works with both pistol-length and carbine-length gas.
Can I use this for home defense?
Yes. The 220gr HP BT delivers 538 ft-lbs of energy and is effective at indoor distances. When suppressed, it also reduces muzzle blast and flash — critical advantages in low-light defensive scenarios.
Is this ammo suppressor safe?
Absolutely. The .300 Blackout was designed for suppressed use, and this load stays well below the speed of sound at 1,050 fps.
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.
