300 AAC Blackout – 125 gr Sierra TMK – Black Hills (D300WHISPERN3) – 500 Rounds

Supersonic 300 Blackout gives a short-barreled rifle real reach, and a match bullet makes the most of it. This listing is Black Hills 300 AAC Blackout 125 grain Sierra Tipped MatchKing ammo, MPN D300WHISPERN3, sold as a 500 round case. It suits shooters who want accurate supersonic 300 BLK for precision practice, steel at distance, and testing what a short rifle can really do. It is also useful for comparing barrel lengths and optics on 300 BLK builds.

Black Hills rates this load at 2,100 fps with 1,224 ft-lbs of muzzle energy. The Sierra Tipped MatchKing is a polymer tipped match bullet with a boat tail and a high ballistic coefficient for its weight, which helps it hold velocity and resist wind beyond typical 300 BLK distances. Black Hills lists it for long range target, precision shooting, and varmint use. As a match bullet it is built for accuracy, so choose a dedicated hunting bullet for deer and hogs.

It fits rifles and pistols chambered in 300 AAC Blackout or 300 Whisper, including AR-15 uppers in 300 BLK, the SIG MCX, Q Honey Badger, Daniel Defense DDM4 300S, Ruger American Ranch, and Savage 110 in 300 BLK. A common question is whether supersonic 300 BLK cycles without a suppressor. Yes. Supersonic loads like this generally run reliably in unsuppressed rifles. Another common question is how far 300 Blackout is effective with match bullets. Many shooters stretch supersonic 300 BLK to 300 yards or more on steel, though trajectory drops quickly beyond that.

Black Hills D300WHISPERN3 is new production ammunition, not reloads, made in the USA by Black Hills in Rapid City, South Dakota. Cases are reloadable brass with boxer primers, and the load is non-corrosive. This listing ships as 25 boxes of 20 rounds for 500 total, all from one lot, which gives you consistent data across many range sessions.