Out of stock
SKU: A4034
UPC: 858767004034
MPN: 00403
Atomic Ammunition's 300 Win Mag Match load pairs a 220-grain Sierra MatchKing hollow point boat tail with new brass and match-grade powder, built for shooters who want repeatable accuracy out of a heavy-for-caliber bullet. This is target and tactical ammunition, not a hunting load, and the heavy MatchKing makes it well suited to long-range precision rifles chambered in .300 Winchester Magnum. Anyone running a bolt gun or precision semi-auto and chasing tight groups past 500 yards will recognize what a 220-grain match bullet does for ballistic coefficient and wind bucking. It ships 20 rounds per box, 10 boxes per case.
The 220-grain MatchKing leaves the muzzle at 2600 FPS and carries roughly 3300 ft-lbs of energy, per published data, giving this load the sectional density and downrange retention that lighter .300 Win Mag bullets can't match. The hollow point boat tail profile is a match design built for consistency on paper, not terminal expansion, which is why Atomic positions it for target and tactical use rather than big game. Brass cases are new and reloadable, and the centerfire primers are loaded for uniform ignition. The heavy bullet and match powder selection are aimed squarely at the precision crowd. If you're cross-shopping heavier .300 magnum options, the 180-grain Fusion load and Hornady American Whitetail sit at the lighter end of the spectrum.
Reach for this load when you're zeroing a long-range .300 Win Mag, training for a precision match, or feeding a suppressed bolt gun where bullet weight and consistency matter more than expansion. The new, reloadable brass also makes it a sensible starting point for handloaders who want quality cases after the first firing. Buyers building out a precision rifle setup often pair match ammo with proper storage, so it's worth looking at our ammo boxes to keep cases organized by lot. Browse more centerfire rifle ammunition when you need to stock additional calibers.
No. This 220-grain Sierra MatchKing load is a supersonic match cartridge leaving the muzzle at 2600 FPS. Atomic does produce a separate subsonic 300 Win Mag line in lighter bullet weights, but this specific load is built for full-power precision and long-range target work, not subsonic suppressed shooting.
Atomic markets this as match target and tactical ammunition. The Sierra MatchKing HPBT is a target bullet designed for accuracy and consistency, not controlled terminal expansion. Per the manufacturer, these bullets may not be appropriate for hunting big game. For hunting, choose a bonded or controlled-expansion bullet instead.
Yes. Atomic loads this match ammunition with new brass and standard centerfire primers, so the cases can be reloaded after firing. The new brass and match-grade powder also make this a quality source of once-fired cases for handloaders working up precision loads.
The 220-grain MatchKing is a heavy-for-caliber bullet with high sectional density and ballistic coefficient. That translates to better wind resistance and energy retention at distance, which is why precision and long-range shooters favor heavier bullets in .300 Winchester Magnum for past-500-yard accuracy.
WARNING ⚠️ You must be 18 or older to purchase shotgun or rifle ammunition and 21 or older to purchase handgun ammunition and firearms. Please reference our requirements for ammunition orders to "restricted" states HERE. Always make sure you use the correct ammunition for your firearms. Ammo cannot be shipped to a PO Box. Please reference state & local laws before making a firearm or ammunition purchase.
