Many cartridges that have become popular with military snipers have also made the jump to outdoor sports (and vice versa). The .300 Winchester Magnum and the .338 Lapua Magnum are among the best examples.

The .338 Lapua Mag. was developed in 1983 as a long-range sniper cartridge, and it was used in the wars in Afghanistan and Iraq. The .300 Win. Mag. wasn’t developed for snipers, per se, but Navy SEAL Chris Kyle famously used a .300 Win. Mag. on his way to cementing his place as a legend among American snipers.

These cartridges aren’t exactly in each other’s weight class, but their popularity in pop culture and the hunting world has earned them high status among commercially available, ultra-powerful cartridges. If you’re looking to kill large game from long distance, which heavy-hitting cartridge should you bring along for the ride?

The .338 Lapua Mag. was designed with the express intent of launching a 250-grain, .338-inch projectile 3,000 feet per second (fps), according to Frank C. Barnes in “Cartridges of the World” (for perspective, an AR-15 shoots a 55-grain projectile about that fast). The necked-down .416 Rigby case can hold a whopping 75 to 100 grains of powder, which helps produce over 4,800 foot-pounds (ft.-lbs.) of energy at the muzzle with a 250-grain bullet.

Barnes notes that the military full metal jacket bullet is “very effective” at 1,500 meters, and Federal’s Trophy Copper load will reliably expand out to 800 yards (1,800 fps) and maintain supersonic velocities out to 1,500 yards.

The .300 Win. Mag. isn’t a lightweight, but it’s hard to compete with the Lapua’s power. The .300 can reach similar muzzle velocities, but it usually does so with a 165- or 180-grain bullet rather than a 250-grain. Federal’s Trophy Copper .300 Win. Mag., for example, uses a 165-grain, all-copper bullet that will reliably expand out to about 700 yards (1,800 fps) and maintains supersonic velocity well past 1,000 yards.

In most practical hunting situations on large North American game animals, hunters likely won’t notice much difference between the Lapua and the Win. Mag. The MeatEater crew can confirm that a .300 Win. Mag. will bring down moose, the largest game animal on North America. But even though the trajectories of each cartridge are similar, the .338 Lapua Mag. delivers more power on very heavy animals and at long distances. Heavy bullets don’t always translate to downed animals, but they sure don’t hurt.

Winner: .338 Lapua Magnum

Just like the .300 Win. Mag. had a tough time competing with the .338 Lapua Mag. from a ballistics perspective, the .338 can’t compete with the .300 on shootability.

First, the .300 Win. Mag. is significantly cheaper. Federal sells 20 rounds of .338 Lapua Mag. Trophy Copper for $96, while a box of .300 Win. Mag. Trophy Copper will only set you back $60. Since .300 Win. Mag. is more popular, ammo companies offer cheaper varieties. Hunters can find a box of .300 Win. Mag. for prices comparable to other big game cartridges, while .338 Lapua Mag. almost always runs in the $5-per-round range. Specific .338 Lapua bullets can also be extremely difficult to acquire during the nationwide ammo shortage.

The .300 Win. Mag. is also more practical on mountain-trekking Western hunts. Only heavy rifles can comfortably accommodate the recoil of a .338 Lapua Mag. With a 9.5-pound rifle, a .338 Lapua Mag. produces about 37 ft.-lbs. of energy, according to Chuck Hawks’ recoil table. A .300 Win. Mag, by contrast, produces only 25 ft.-lbs. of energy using an 8.5-pound rifle—which is still enough to knock smaller shooters off their feet.

Anyone who has lugged a rifle up and down a mountain can see the trade-offs. A .338 rifle that’s heavy enough to match the recoil of a .300 Win. Mag would be far too heavy to carry great distances. Hunters might feel stuck hunting lower elevations and could have less luck bagging game. A lightweight .300 Win. Mag. might produce recoil similar to a 9.5-pound .338 Lapua Mag. rifle, but could allow hunters to cover more ground in search of animals.

You might have a superhuman ability to place accurate shots under heavy recoil. If that’s you, or you cover ground primarily with a 4×4, the .338 might be a good bet. But for most hunters, recoil affects shot placement, especially when shooting from awkward field positions. In that case, the .300 Win. Mag. is a much better option.

Winner: .300 Win. Mag.

Versatility refers to the range of bullet weights available (and the game appropriate to those weights) and the range of firearm options chambered to that specific cartridge.

Since the Lapua was designed for a 250-grain bullet, most loads use either that bullet or a 300-grain pill. Sometimes manufacturers will load 230-grain or 285-grain projectiles, but Federal’s selection of 250- and 300-grain bullets is typical.

The .300 Win. Mag. offers a much wider variety of options. Barnes lists bullets ranging from 110-grain hollow-points to 220-grain open-tip match. Federal offers 25 varieties of .300 Win. Mag. using bullets ranging from 150-grains to 215-grains. The lighter bullets would be more appropriate for whitetail, while the heavier, Trophy Bonded or Trophy Copper bullets would work for any North American big game animal.

Less expensive ammunition and a longer track record means that the .300 Win. Mag. can be used in a wider variety of firearms. Both cartridges are chambered primarily in bolt-action rifles, though some lesser known companies make semi-auto guns. But you’re much more likely to find a .300 Win. Mag. at your local sporting goods store than its larger cousin.

Weatherby, for example, chambers their high-end Mark V in .300 Win. Mag. and .338 Lapua Mag., but their less expensive and more popular Vanguard line does not include a .338 Lapua Mag. chambering. Searching most online gun dealers for these two calibers brings up eight or 10 times more options for the .300 than the .338.

Winner: .300 Win. Mag.

And the Winner Is…
For most hunting situations, the .300 Win. Mag. is going to do a better job bringing home game. The .300 Win. Mag. has more than enough juice to get the job done on any animal in North America at reasonable hunting distances. Plus, less expensive and more available ammo allows you to thoroughly practice.

If you plan on making shots from 800-plus yards and you don’t mind super-heavy recoil, or you don’t plan on moving much during your hunt, the .338 Lapua Mag. might be the way to go. For the rest of us, the .300 Win. Mag. will work just fine.

Overall Winner: .300 Win. Mag.