.338 Lapua Mag. Ackley Improved Load Data

Caliber Overview

The .338 Lapua Magnum Ackley Improved (.338 LM AI) is a custom wildcat cartridge designed to increase the powder capacity of the standard .338 Lapua Magnum by blowing out the sidewalls and steepening the shoulder to 40 degrees. As a custom chambering, specific dimensions can vary based on the reamer used, but it generally operates at higher pressures than standard factory ammo to achieve improved velocity.