The .338 Lapua By Chuck Hawks The giant .338 Lapua Magnum dates back to 1983, when it originated as a U.S. military project. The design goal was a 250 grain bullet at 3000 fps for long range sniping, a role in which the .338 Lapua has proven very effective. Ballistically, it is much like, but slightly inferior to, the .338-378 Wby. Mag. Lapua factory loads drive a 250 grain Lock Base soft point bullet at a MV of 2974 fps, or a 275 grain A-Frame bullet at a MV of 2581 fps. The 8.58x71mm military load uses a 250 grain spitzer-boat tail FMJ bullet at a MV of 2950 fps with muzzle energy (ME) of 4830 ft. lbs. This round is considered effective for sniping at 1500 meters, an achievement that has no application for sporting purposes. In fact, unless you are a military sniper or an assassin, the .338 Lapua cartridge has no practical application. There are several more practical .338 caliber hunting cartridges. According to the fifth edition of the Hornady Handbook of Cartridge Reloading (which is more conservative than some) a 225 grain Hornady Spire Point hunting bullet can be driven at a MV of 2500 fps by 80.7 grains of Winchester WMR powder, or to a MV of 3000 fps by a maximum load of 95.4 grains of WMR. The ME of the latter load is 4496 ft. lbs. At 200 yards the energy is an impressive 3212 ft. lbs., and at 400 yards the retained energy amounts to 2236 ft. lbs. Zero that load at 300 yards and the trajectory looks like this: +3.5" at 100 yards, +4.6" at 200 yards, 0 at 300 yards, and -11.1" at 400 yards. (Hornady figures taken from the 24.5" barrel of a Sako 995 rifle.) Note: A complete article about the .338 Lapua can be found on the Rifle Cartridge Page. |
Copyright 2004, 2016 by Chuck Hawks. All rights reserved.
|