GECO ZERO – How the Lead-Free Bullet with Dual Tin Cores Is Made

Dear GECO fans,

Today, our product development team offers an exclusive behind-the-scenes look into the manufacturing of the lead-free GECO ZERO bullet.

Imagine this: fine tin wire is precisely drawn to form the core material. At the same time, the robust bullet jacket is formed from tombac-coated mild steel. Every component is assembled with care to create a bullet known for accuracy and penetration.

Tin Wire & Cup

Before production begins, the main components—jacket and cores—are prepared.
Unlike traditional single-core bullets, GECO ZERO features two tin cores made from custom-drawn wire:

• The rear core is weight-stable and ensures reliable exit wounds.

• The front core is pre-fragmented, ensuring rapid expansion inside the game—even at extended distances.

The precise manufacturing of these components is key to quality assurance and upholding GECO’s high standards.

Jacket Drawing & Core Preparation

The GECO ZERO consists of two tin cores and a tombac-plated mild steel jacket.

1. Deep Drawing the Jacket:
   The preformed cup undergoes a two-step deep drawing process:

   • First, the cup is initially drawn.

   • Then, the jacket is brought to its final length and thickness.
     Since irregularities can occur at the mouth, the jacket is drawn longer and trimmed afterward.

2. Preparing the Cores:
   While the jackets are cleaned, the tin wires are cut, pre-pressed, and cleaned on a separate machine—ready for bullet assembly.

Bullet Assembly

The assembly follows a multi-step process:

1. The rear tin core is inserted and the bullet base is formed.

2. The front tin core is then pressed into place.

3. The bullet is shaped to its final geometry, the cannelure is added, and the projectile is calibrated.

Each bullet undergoes a rigorous quality check, including test firing, to ensure performance in later loading processes.

GECO ZERO Features

The special jacket design minimizes barrel fouling and allows for easy combination with other jacketed bullets of similar material.
Thanks to its fast response characteristics, GECO ZERO is especially suitable for light to medium game. Its pre-fragmented front core ensures reliable expansion, even at long distances.