.338 Lapua Magnum Ammo Tray System

A simple and efficient tray system for organizing .338 Lapua Magnum cartridges inside a standard M2A1 .50‑cal ammo can. The tray geometry is designed to CIP specifications, supporting cartridges up to a maximum overall length of 93.5 mm + 1 mm clearance.

If your handloads exceed the CIP maximum overall length, please use my non‑CIP version of the model, which supports cartridges up to 97.5 mm.

Each tray holds 21 rounds lying flat, with proper support at the case necks to keep them securely in place. No rattling, no loose movement – just clean, compact storage. Cartridges remain easy to remove: a light press on the bullet tip lifts the base out of the tray for quick access. A .50‑cal can accommodates up to 10 trays, for a total of 210 rounds per box.

The trays are designed for straightforward handling. All trays except the top one have small integrated handles, making it quick to grab and lift them out of the box. The top tray is handle‑free so it doesn’t interfere with the lid. Because many ammo cans have a raised or uneven floor, a spacer is included to create a flat, stable base for the bottom tray.

The parts should be printed with supports to ensure clean handle geometry. The model is large and will fit only on printers with a large printbed, such as the H2-series.

Printed in PETG, the trays are robust enough for regular range and storage use. For long‑term storage in a car trunk or other hot environments, ASA is recommended for better heat resistance.

Recommended quantities to print:

• 1× bottom spacer
• 1× top tray without handles
• 9× standard trays with handles

This tray system is modeled to the official CIP maximum dimensions for the respective caliber. The cartridges visible in the preview images are 3D printed dummy rounds, since I do not have access to original ammunition in that caliber; they are only used to demonstrate the fit and appearance.