AMMO: 338 LaPua – Discussion & Facts

  • Understanding Ammunition for Your Hunt
  • Compare ballistic coefficient, velocity, energy and momentum – a Discussion

By Andrew Chamberlain (Creator of “Chamber-It” on Facebook)

The 338 Lapua is a cartridge with a huge fan base.

One almost does not need to introduce or say much about it. I will say this about the 338 Lapua, it is as capable and as impressive as people say it is.  There are a lot of other cartridges that do what people say the 338 Lapua does well, but what makes the 338 Lapua so unique? Not necessarily what it does, but what it does uniquely. I believe everyone can appreciate what makes the 338 Lapua so special and also recognize the hype that also causes some of the descending opinions.

The Lapua can push a very high ballistic coefficient (B.C.) bullet at a fairly decent muzzle velocity for a very long distance. That is, in my opinion, the simplified version of much of the hype (that is true), but may not be put in proper context.

Look at the 300 Win Mag and what it can do with high B.C. projectiles. Then look at the 7mm and even the 6.5mm cartridges. Suddenly the 338 Lapua may not look quite as impressive. Then consider the fact that the projectile can weigh from 250 – 300 grains (not 208, 180, 160 or even 129 grains, but 300). Then consider the momentum this projectile still carries, even when the drop in velocity is so dramatic that the energy has dropped from 5,000 ft-lbs to 590 ft-lbs (this is the approximate energy when a 300 grain projectile transitions to subsonic velocity…less than 1,000 ft/sec). It will still have 43 lbs-ft/sec momentum, which is slightly more than a hot-loaded 357 magnum with a 180 grain slug delivers at the muzzle. Also consider that a 250 – 300 grain 338 caliber bullet is quite long and heavy, which provides great stability in flight through wind, and fog. It even gives a good fight against the rain.

Many look at the 338 Lapua as the ultimate big game and dangerous game cartridge. This may not be a very good argument. Though the 338 Lapua gives a marked improvement over the 338 Win Mag and it gives a slight numerical improvement over the 375 H&H (which initially sounds like something). However, finding a controlled expansion copper or solid flat nose 300 grain 338 caliber slug can be very hard to do (though they do exist). Then comparing the 338 Lapua to the likes of a 416 Rigby, 404 Jeffery, 458 Win Mag or 458 Lott, the comparison starts to be a bit silly.

So in short, don’t just look at the stats. The numerical nature of ballistics or the “hot points” thrown at the consumer can at times only tell half the story. And sometimes tell even less. The 338 Lapua is an impressive cartridge and is very good at doing a handful of things, but it is often touted as the best at something that it may not be intended to be used for at all.

The Ammo Performance Specs poster is a hand-picked selection of some of the most popular hunting cartridges and represent velocity, energy, momentum and recoil for each cartridge in a bar graph with numeric value. Accurately compare one cartridge with similar cartridges of interest. Click on the poster to order.

Factory Load vs. Hand Load The 338 Lapua is one of those rare cartridges where Factory Loads and Hand Loads compete very well with each other. However, hand loading does give a slight edge (20-80 ft/sec) over factory loads in common bullet weights. For some, this minimal difference does not merit hand loading, for others, this little extra, as well as the control and consistency they can derive, make it all worth it. One could mention availability and economics as well.

Quick Ballistics – 338 LaPua

  • Bullet weight = 180 – 300 grains
  • Bullet Velocity = 3,450 – 2,600 ft/sec
  • Optimal Load; Precision => 300 grains @ 2,750 ft/sec = 5,036 ft-lbs Energy & 117.9 lbs-ft/sec Momentum.
  • Hunting => 250 grains @ 3,100 ft/sec = 5,334 ft-lbs Energy & 110.9 lbs-ft/sec Momentum

Comparative Ballistics w/338 LaPua

  • 338 Win Mag: 250 grains @ 2,690 ft/sec = 4,016 ft-lbs Energy & 96.1 lbs-ft/sec Momentum
  • 340 Weathrby: 250 grains @ 2,960 ft/sec = 4,863 ft-lbs Energy & 105.6 lbs-ft/sec Momentum
  • 338 Lapua: 250 grains @ 3,100 ft/sec = 5,334 ft-lbs Energy & 110.9 lbs-ft/sec Momentum
  • 375 H&H: 270 grains @ 2,870 ft/sec = 4,937 ft-lbs Energy & 110.7 lbs-ft/sec Momentum
  • 378 Weathrby: 270 grains @ 3,1800 ft/sec = 6,061 ft-lbs Energy & 122.7 lbs-ft/sec Momentum
  • 416 Rigby: 400 grains @ 2,565 ft/sec = 5,842 ft-lbs Energy & 146.6 lbs-ft/sec Momentum
  • 458 Lott: 500 grains @ 2,350 ft/sec = 6,130 ft-lbs Energy & 167.9 lbs-ft/sec Momentum

The 338 Lapua is a great cartridge and is highly capable of a lot of things. Keeping it in proper context of usage allows one to see what is truly neat or impressive about this cartridge.

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