Passion for Precision

The story of .338 Lapua Magnum, pt 1

19.02.2021

In this two-part feature, we share the background behind the legendary .338 Lapua Magnum and how it came to be a cartridge from Finland, even though the idea was born on another continent.

The .338 Lapua Magnum caliber originates back almost forty years to 1982, when the .338/416 cartridge was developed for the United States military purposes. Officially, the project was to develop a target rifle and cartridge for 1000 yards, but in reality the purpose was more likely to develop a 1500 meter sniper rifle.

The .300 Winchester Magnum and other commercial cartridges did not meet penetration requirements, so the search for a heavier caliber with better ballistics was on. The result was a new wildcat cartridge that was originally formed from a necked down .378 Weatherby Magnum case, and finally from the .416 Rigby case. The new cartridge was known as the .338/416 or 8.58×71.

Lapua finished development of the first bullets and cases for the .338/416 cartridge in 1985. Its first .338 caliber projectile was the B408, which in 1985 looked more like a D46 bullet on steroids than the Lock Base type currently produced.

In 1986, the .338/416 cartridge with a Lapua bullet and case won the 1,000 yard navy rifle competition in Quantico, Virginia. In spite of that, the U.S. military selection criteria went in a different direction. At that point, Lapua was left more or less alone with the new caliber cartridge, still management decided to continue product development. This resulted in specifying the measurements, and the cartridge was named the .338 Lapua Magnum. The .338 Lapua Magnum was slightly different than the original .338/416 case. Case and chamber dimensions were modified, along with the interior structure of the case to withstand higher chamber pressures than the .338/416 design. The .338 Lapua Magnum had arrived.

Continued in part 2!