Ask an elk guide about the 338 Win Mag and you’ll likely hear about big bulls and moose dropped in timber. It is a heavy-bullet magnum built for large game at sensible range. This guide covers 338 Win Mag ballistics for the load we carry, then puts it next to the 300 Win Mag and 338 Lapua. You’ll also learn how to read the specs and choose a bullet.
What Is a 338 Win Mag?
Winchester introduced the .338 Winchester Magnum in 1958. It is a belted magnum made from the .458 Winchester Magnum case necked down to hold a .338 inch bullet. It fits in a standard-length rifle action, so rifles for it are not overly long or heavy.
It was built for big North American game: elk, moose and large bears. It fires heavier bullets than the .30 caliber magnums, which many hunters like for big, tough animals.
338 Win Mag Ballistics: Our Load
We stock one load for this cartridge, a lead-free copper hunting round from Hornady.
| Load | Grain | Bullet | Velocity (fps) | Energy (ft-lb) | Pack |
|---|---|---|---|---|---|
| Hornady Outfitter | 225 | CX copper polymer tip | 2,800 | 3,917 | 20-round box |
Hornady Outfitter 338 Win Mag 225 grain CX lists 2,800 fps and 3,917 ft-lb. Hornady lists a G1 BC of 0.49 and a sectional density of 0.281. The case is sealed against moisture, which suits wet hunts in the backcountry.
The CX is a monolithic copper alloy bullet. It does not have a lead core, so it holds its weight as it expands. That design suits elk and moose and meets lead-free rules where they apply. Hunting rules vary, so check your state’s regulations.
338 Win Mag vs 300 Win Mag and 338 Lapua
Here is how our 338 Win Mag load lines up with hunting loads from its two closest neighbors.
| Load | Grain | Bullet | Velocity (fps) | Energy (ft-lb) |
|---|---|---|---|---|
| Barnes VOR-TX 300 Win Mag | 180 | TTSX copper | 2,960 | 3,503 |
| Hornady Precision Hunter 300 Win Mag | 200 | ELD-X | 2,850 | 3,607 |
| Hornady Outfitter 338 Win Mag | 225 | CX copper | 2,800 | 3,917 |
| Swift A-Frame 338 Lapua | 250 | Bonded round nose | 2,900 | 4,671 |
| Hornady Precision Hunter 338 Lapua | 270 | ELD-X | 2,800 | 4,699 |
A few points stand out:
- Against the 300 Win Mag: Barnes VOR-TX 300 Win Mag 180 grain lists 2,960 fps and 3,503 ft-lb. The 338 Win Mag load is a bit slower but carries a heavier, wider bullet and more energy at the muzzle.
- Against the 338 Lapua: the Lapua is a much larger case. Hornady Precision Hunter 338 Lapua 270 grain lists 2,800 fps and 4,699 ft-lb. It needs a longer, heavier rifle and makes more recoil.
What is the difference between 338 Lapua and 338 Win Mag? Both fire .338 inch bullets. The Win Mag is a belted hunting round for standard-length actions. The Lapua is a larger, rimless round first built for long-range military use. See our 338 Lapua Magnum ballistic data guide and our 300 Win Mag ballistic data guide for more detail.
How to Read Velocity, Energy and BC
Velocity is muzzle speed in feet per second. Higher speed means a flatter path and less time for wind to push the bullet.
Energy is muzzle energy in foot-pounds. It comes from bullet weight and the square of speed. Big game calls for a good amount of energy, but bullet build decides how that energy is used.
BC shows how well the bullet holds speed. A higher number means less drop and drift at range.
Sectional density compares bullet weight to its diameter. Higher sectional density tends to mean deeper penetration, all else equal. That’s one reason heavy .338 bullets have a good name on large game.
Which Bullet Weight for Which Game?
- Deer and pronghorn: the 338 Win Mag is more than you need. A lighter round will do the job with less recoil.
- Elk: 210 to 250-grain bullets built to hold together. Our 225-grain CX fits here.
- Moose and large bears: 225 to 250-grain bonded or copper bullets.
Practice matters as much as the round. Recoil is stout, so put in range time with your hunting load. A well-placed shot from a rifle you shoot well beats a bigger round you flinch from.
Barrel Length and Conditions
Many 338 Win Mag hunting rifles have barrels around 24 to 26 inches. A shorter barrel will give up some speed. Cold mornings can slow some powders. High altitude, common on elk hunts, thins the air and helps the bullet hold speed. Treat the 338 Win Mag ballistics on the box as a starting point. Chronograph your rifle and confirm drop at the ranges you plan to shoot.
Shop 338 Win Mag Ammo
Find our load in the 338 Win Mag ammo collection. For more magnum options, browse our 300 Win Mag ammo and 338 Lapua ammo.
Frequently Asked Questions
What is a 338 Win Mag?
The .338 Winchester Magnum is a belted rifle cartridge introduced by Winchester in 1958. It is based on the .458 Winchester Magnum case necked down to a .338 inch bullet. It is a big-game round for elk, moose and large bears.
What is the difference between 338 Lapua and 338 Win Mag?
Both fire .338 inch bullets. The 338 Win Mag is a belted hunting round that fits a standard-length action. The 338 Lapua is a larger rimless case first built for long-range military use. It pushes heavier bullets at similar or higher speed but needs a bigger rifle.
Which bullet is best for a 338 Win Mag?
Pick the bullet for the game. For elk, moose and bears, use a 210 to 250-grain bonded or copper bullet that holds together. In our stock, Hornady Outfitter 225 grain CX is a lead-free copper option.
What velocity does a 225 grain 338 Win Mag bullet reach?
Hornady Outfitter 338 Win Mag 225 grain CX lists 2,800 fps at the muzzle. Your rifle may run a bit faster or slower based on barrel length and conditions. A chronograph gives you the real figure.
How accurate is a 338 Win Mag?
A good rifle and load can shoot tight groups. The bigger limit for most people is recoil. Shooters who flinch lose accuracy fast. Practice with your hunting load, use a solid rest and consider a good recoil pad.
