Underwood Ammo‘s Subsonic loading in 8.6 Blackout (brand part no. 951) drives a 300-grain Custom Competition hollow point boat tail bullet at a listed 950 feet per second for shooters running a suppressed rifle built around this larger-diameter Blackout cartridge. 8.6 Blackout was designed specifically to stabilize heavy, subsonic bullets more efficiently than smaller-diameter cartridges can, and this 300-grain loading sits right in the sweet spot the round was built around. The hollow point boat tail combines an open tip for reliable expansion with a tapered base that keeps the bullet stable well below the speed of sound. The case material is nickel-plated brass, adding corrosion resistance for ammunition that may sit loaded for a while between range trips. For 8.6 Blackout shooters running suppressed, this rifle ammunition is built for exactly that role.

Key Specifications

• The chambering is 8.6 Blackout, a larger-diameter cartridge built to stabilize heavy subsonic bullets.
• The bullet weighs 300 grains, matched to the cartridge’s subsonic design intent.
• The bullet is a Custom Competition hollow point boat tail (HPBT).
• Muzzle velocity is listed at 950 fps, comfortably subsonic for quiet, suppressed shooting.
• The boat tail base helps the bullet stay stable at subsonic speed, where a flat-base bullet can lose accuracy.
• The case material is nickel-plated brass, adding corrosion resistance over standard brass.
• Cost runs about $2.83 per round, in line with premium subsonic specialty ammunition.
• Each box holds 20 rounds, a standard count for a range session.
• Shipping weight per box runs 1.46 pounds, useful for shooters ordering multiple boxes.
• The retail box measures about 6.15 inches, a compact package for shelf storage.

Frequently Asked Questions

Why was 8.6 Blackout designed around heavy bullets? Its larger case diameter stabilizes heavy, subsonic-weight bullets more efficiently than smaller cartridges, keeping them accurate well below the speed of sound.

Is this ammunition meant for suppressed shooting? Yes, at a subsonic 950 fps, it’s built specifically for quiet, suppressed rifles.

Why nickel-plated brass instead of standard brass? Nickel plating resists corrosion better than bare brass, useful for ammunition stored loaded between range trips.

Buy Underwood Subsonic 8.6 Blackout 300gr Hollow Point Boat Tail

A suppressed rifle is only as quiet as the ammunition running through it, and this 300-grain subsonic load is tuned specifically for that job. Order from our Lubbock, Texas gun shop and it ships fast to your door.