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.338 Lapua Mag. Ackley Improved Load Data

Alternative names:

Our load data for caliber .338 Lapua Mag. Ackley Improved covers 372 bullets from 35 manufacturers and a total of 23436 load recipes.

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.

Suitable Powders

Bullet Weight (gr) ->
0-50
50-75
75-100
100-150
150-200
200-300
>300

👍 ... suitable powder 

👍👍 ... suitable AND popular powder among our reloading community  (clasification might evolve as more community members share their loads )

Caliber Specifications

Standard / Datasheet

Wildcat

Primer Size

Large Rifle Magnum (LRM)

Case Capacity

124.89 Grains of Water

Bullet / Barrel Diameter

0.338'' | 8.59 mm

Max. Case Length

2.724'' | 69.19 mm

Max. Cartridge Length 

3.975'' | 100.97 mm

Max. Standardized Pressure:

69618 psi | 4800 bar

XXL ID

CID_452

.338 Lapua Mag. Ackley Improved load data is available with the following bullets:

(most popular first)

Filter by Bullet Weight (Grains)

Weight vs. Velocity - Suitable Bullets for this Caliber

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Barrel Length  Variation vs. Velocity - by Bullet Weight

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