338 Lapua Magnum vs. 50 BMG: Extreme Long-Range Cartridges

These two military rounds take the concept of long-distance shooting to a new level: the 338 Lapua Magnum, and the 50 BMG.

The 50 Browning Machine Gun (aka 50 BMG, .50 Cal, 50 Browning, or 12.7x99mm NATO) is the longest-serving centerfire cartridge in the U.S. military. The 338 Lapua Magnum is a relative newcomer to the long-range shooting scene.

Although initially developed for military use, the 338 Lapua Mag and 50 BMG have found a home with civilian shooters for long-range hunting and F-Class shooting competitions.

Let’s evaluate the 50 BMG vs. 338 Lapua to help you understand the differences between the two rounds and give you a clearer idea of which is better for your long-range shooting needs.

What Is the Difference Between .50 Cal and 338 Lapua Magnum?

The key difference between 50 BMG and 338 Lapua Magnum is this: the 50 BMG is the bigger cartridge, and appropriately fires a larger, heavier bullet with more kinetic energy. Although the 338 Lapua has considerably less case capacity than the 50 BMG, both rounds have similar muzzle velocities.

Cartridge Specs

Perhaps the most obvious difference between these two rounds is their size. The 50 BMG’s case length towers over 338 Lapua Mag’s: 3.910” compared to 2.724”. The disparity only increases in terms of overall length. The 50 BMG measures 5.450”, whereas the 338 Lapua has a maximum overall length of 3.681”.

The 50 BMG fires a considerably larger projectile, with a diameter of 0.510” compared to the 338 Lapua’s 0.338”.

Civilian 50 BMG factory ammo is typically loaded with bullets weighing between 650 and 750 grains, while the 338 Lapua is generally loaded with 200 to 300 grain bullets.

Those massive bullets require a lot of powder to propel them down the barrel. The 338 Lapua’s case capacity is larger than most rifle cartridges at 114.2 grains H2O. Still, that’s not very much compared to the 50 BMG’s 292.8 gains.

Recoil

The 50 BMG’s massive case capacity and projectiles come at a cost: massive recoil. That’s a major reason why many shooters prefer the smaller 338 Lapua.

It is impossible to perform a pure apples-to-apples recoil comparison, as both cartridges are fired in very different firearms. That being said, we can objectively compare the rounds’ free recoil, which is a function of four factors: muzzle velocity (fps), propellant charge weight, bullet weight, and firearm weight.

For 50 BMG, we will consider the Barrett Model 82 semi-automatic sniper rifle weighing a whopping 32.7 pounds. For the 338 Lapua, a McMillan Tac-338 bolt-action rifle weighing 13 pounds.

For ammo, we will compare standard military issue 50 BMG M33 ball 660 grain FMJ (2,910 fps muzzle velocity) and 338 Lapua Mag Lapua 250 grain Lock Base FMJ (2,952 fps).

Given these rounds, the 338 Lapua has free recoil of 36.5 ft-lbs. The 50 BMG, 82.7 ft-lbs. In no uncertain terms, the 50 BMG has more than double the free recoil of 338 Lapua Mag.

To put these massive recoil numbers in perspective, an average 308 Winchester load has around 20 ft-lbs of free recoil.

The amounts of recoil produced by the 338 and the 50 BMG are so excessive that virtually every rifle chambered for either comes with a factory-installed muzzle brake. Without it, most shooters would not be able to fire accurately.

Many expert shooters will tell you that the recoil of these rounds is manageable, although that comes from years of training and acclimatization. Learning how to fire these cartridges accurately takes time, as their recoil can easily cause inexperienced shooters to develop a flinch.

Most shooters understand what they’re getting into when they make the decision to purchase a 50 BMG rifle. If you aren’t already experienced with it, then it would be wise to consider professional training to learn how to handle such a mighty round’s recoil.

Muzzle Velocity, Kinetic Energy, and Trajectory

The 338 Lapua may have half the recoil, but how does it compare to the 50 BMG ballistically?

For this comparison, we will analyze three rounds for each cartridge. The 50 BMG rounds are Hornady Match 750 grain A-MAX (G1 BC 1.050), PMC Bronze 660 grain FMJ-BT (G1 BC 0.701), and PMC X-TAC Match 740 grain (G1 BC 0.909). For 338 Lapua Magnum, the Hornady Custom 240 grain CX (G1 BC 0.611), Hornady Match 285 grain ELD Match (G1 BC 0.789), and Prvi Partizan 250 grain FMJBT (G1 BC 0.606were selected.

A 500 yard zero was used, but the 50 BMG was with a 36 inch barrel and the 338 Lapua was with consideriderably shorter 24 and 27 inch barrel.

Ballistic Coefficient and Sectional Density

Ballistic coefficient (BC) is a measure of how aerodynamic a bullet is and how well it will resist wind drift. Sectional density (SD) is a way to evaluate the penetration ability of a bullet based on its weight and diameter.

The 50 BMG has some of the highest BC values of all centerfire rifle cartridges, with heavier bullets having a BC over 1.0. The 750 grain A-MAX bullet evaluated earlier has a BC of 1.05, while the 660 grain FMJ has a BC of 0.701. In comparison, the 338 Lapua loads have BCs of 0.625 and 0.720 for the 250 and 300 grain loads, respectively.

Narrower bullets typically have an advantage when it comes to SD, as they can focus all their energy onto a more localized area. However, the 50 BMG’s bullets are so much heavier that they brute force their way to higher SD values.

For example, the 50 BMG 750 grain A-MAX bullet has an SD of 0.412; the 660 grain FMJ, 0.357. In contrast, the 338 Lapua 300 grain AccuBond has an SD of 0.375, falling right in the middle of the two .50 cal rounds.

Which is Better for Hunting?

The 338 Lapua and 50 BMG affirmed their long-range shooting capabilities during the recent wars in Iraq and Afghanistan. However, their use for big game hunting is a relatively new development.

There’s no question that 50 BMG ballistics are impressive. No animal on the planet can stand up to it. However, the .50 cal has several downsides when it comes to hunting.

Read full comparison ➜ https://ammo.com/comparison/338-lapua-vs-50-bmg

Source: https://freedombunker.com/2025/10/24/338-lapua-vs-50-bmg/