Two of the rifles that extreme long-range shooters are going to have to put under the microscope before making a purchase are the McMillan TAC-338a and ArmaLite AR-50A1.
This also means that shooters will be considering the virtues (and vices) of two cartridges, the .338 Lapua and the .50 BMG.
So here’s what you need to know from a very high level.
Cost and Availability
Both the .338 Lapua and .50 BMG are serious extreme long-range cartridges and given the niche (and the amount of in-demand metals needed to manufacture them) they are quite expensive.
No matter how you slice it or where you get your ammo, you will be dropping the hammer not only on a primer but on a few dollars when you pull the trigger.
Now, just how much either of these cartridges costs is a function partially of the bullet and load data, but even with that being said, .338 Lapua is pretty much unequivocally more affordable.
Expect per-round costs of .338 Lapua to be somewhere around $4 to $8 per round, with an average price somewhere around $6.
As for .50 BMG, price also varies but you can expect your per-round cost to be somewhere between $11 and $20 (and in some cases even higher).
Bullet Weight, Muzzle Velocity and Energy
It goes without saying that the .50 BMG is loaded with a larger, heavier bullet. Typical weights for .50 BMG bullets range from 647 to 750 grains, whereas for the .338 Lapua bullet weights range between 200 and 300 grains – this is a massive difference.
As for muzzle velocity, the .50 BMG is usually around 2800 FPS but can be as high as 4000 FPS. For the .338 Lapua, muzzle velocities usually range between 2800 and 3500 FPS, which is fairly comparable.
Given this information, it is clear that the muzzle energies delivered by most .50 BMG rounds are considerably higher than those of the .338 Lapua. The .50 BMG usually produces muzzle energy around 13000 to nearly 14000 ft-lbs, whereas .338 Lapua usually produces muzzle energy between 4600 and 4800 ft-lbs.
As a result, recoil associated with .50 BMG is much higher. However, guns chambered in .50 BMG, like the ArmaLite AR-50A1, are usually very heavy and outfitted with muzzle brakes, so recoil is not nearly as bad as you might expect it to be.
Downrange Performance
Both of these cartridges are heavy hitters that offer excellent downrange performance, but for the purposes of this exposition we will look at two factors: drop and retained energy.
Assuming a .338 Lapua cartridge loaded with a 250 grain bullet that left the muzzle with 4830 ft-lbs of energy at 2950 FPS, it would retain just over 1500 ft-lbs of energy at 1000 yards and would drop by just over 264”.
As for .50 BMG, assuming a cartridge loaded with a 660 grain bullet leaving the muzzle at 3080 FPS and carrying 13900 ft-lbs of energy, that bullet would retain 5080 ft-lbs of energy at 1000 yards and would drop by just under 227”.
Interestingly, the .50 BMG is slightly flatter shooting, but it loses kinetic energy a little bit faster, too. Even so, it retains significantly more energy when it reaches its target, which is something to keep in mind.
Where to Learn More About the McMillan TAC-338a and Other Extreme Long-Range Rifles
Are rifles like the McMillan TAC-338a and ArmaLite AR-50A1 still in contention for your consideration? If you’re in the market for an extreme long-range rifle, consider one of these – you can learn more about both (and other long-range rifles) online at B&B Firearms.com. They carry both (and others) and offer attractive, interest-free payment plans on select models
