Atomic 300 Win Mag 220gr Match – Superb Long Range Ammo

Description

Most 300 Winchester Magnum ammunition is built for hunting, and the few match loads that exist usually stop at 190 or 200 grains. The Atomic 300 Win Mag 220gr Match goes heavier. A 220 grain Sierra MatchKing at 2600 feet per second is a specialist load for shooters who care about what the bullet is doing at a thousand yards rather than at three hundred.

• Why the heaviest bullet wins at distance
• Full specifications
• Twist rate, and this one really matters
• Honest notes before you buy
• Barrel life and recoil, stated plainly
• The bottom line

Why the heaviest bullet wins at distance

Ballistic coefficient is what determines how well a bullet fights air, and in any given caliber the heavier bullets generally have the higher numbers. The 220 grain MatchKing in the Atomic 300 Win Mag 220gr Match carries one of the best coefficients available in 30 caliber, which translates directly into less wind drift where wind is the thing that beats you.

The tradeoff is velocity. At 2600 feet per second the Atomic 300 Win Mag 220gr Match starts slower than a 180 grain load by several hundred feet per second, and inside 300 yards the lighter bullet shoots flatter. Past 600 the heavy bullet has caught up, and past 800 it is comfortably ahead.

Full specifications

• Caliber: 300 Winchester Magnum
• Bullet weight: 220 grain
• Bullet: Sierra MatchKing hollow point boat tail
• Muzzle velocity: 2600 fps
• Muzzle energy: 3300 ft-lbs
• Ballistic coefficient (G1): among the highest available in 30 caliber, which is the reason this bullet exists
• Case: reloadable boxer primed brass
• Quantity: 20 rounds per box
• Part number: A4034, 20 rounds per box

3300 foot pounds at the muzzle is substantial, and because the bullet holds velocity so well it stays meaningful a long way out. That retained energy is why heavy 30 caliber match loads remain relevant for extended range work even as the 6.5s and the 338s have taken attention away.

Twist rate, and this one really matters

A 220 grain 30 caliber bullet is long, and long bullets need spin. You want a 1 in 10 inch twist and ideally faster to stabilize the Atomic 300 Win Mag 220gr Match properly. Many 300 Win Mag rifles are cut 1 in 10, which works, but some older barrels are 1 in 12 and those will not stabilize this bullet.

Check your barrel before ordering. If you are not sure, fire a group at a hundred yards with the Atomic 300 Win Mag 220gr Match and look at the holes in the paper. Clean round holes mean it is stabilizing. Oval or keyholed holes mean the bullet is tumbling and you want a lighter load instead.

Honest notes before you buy

This is expensive ammunition and twenty rounds does not go far in a long range session. Most people shooting at this level handload, and the brass from the Atomic 300 Win Mag 220gr Match is a good starting point for that. Save every case.

Do not hunt with it. A MatchKing hollow point is an accuracy design, not an expanding bullet, and the small tip cavity exists to shift the center of gravity rather than to open on impact. On game it frequently passes straight through. Use the Atomic 300 Win Mag 220gr Match on paper and steel and buy a proper hunting bullet for anything alive.

Barrel life and recoil, stated plainly

The 300 Winchester Magnum burns a lot of powder and throats erode. A competitive shooter running the Atomic 300 Win Mag 220gr Match at volume should expect to be watching accuracy after a couple of thousand rounds. That is the price of the performance and it is worth knowing before you build a season around the cartridge.

Recoil is significant and a 220 grain bullet does not help. In a heavy precision rifle with a brake the Atomic 300 Win Mag 220gr Match is manageable and you can spot your own impacts. In a light hunting rifle it will move you enough that you will not, which defeats the purpose of shooting at distance in the first place.

The bottom line

For long range precision work with a 300 Winchester Magnum, the Atomic 300 Win Mag 220gr Match is a serious factory load built around the right bullet for the job. You can read more about the bullet design at swiftbullets.com, or browse the rest of our stock on the MAG5 Firearms ammunition page.

MAG5 Firearms keeps the Atomic 300 Win Mag 220gr Match in stock and moving, and we are glad to talk through bullet choice before you order. If you are working up a load for a new rifle, a single box of the Atomic 300 Win Mag 220gr Match is a sensible place to start.