The Shooters Box 12GA to 9MM Adapter

Convert your break-open shotgun into a dual-caliber field tool with The Shooters Box 12GA to 9MM Adapter. Precision CNC machined from high-quality stainless steel to exact 2¾" 12-gauge shell dimensions, this adapter drops straight into your barrel and chambers any standard 9mm Luger (9×19) round — no modifications required.

Key Features

• Rifled bore for improved 9mm accuracy — not a smooth-bore design
• SAAMI-spec CNC-machined chamber for reliable feeding with any 9mm Luger ammunition
• Stainless steel construction — durable, corrosion-resistant, field-ready
• Fits any break-open shotgun with 2¾" or 3" chambers
• Adapter orientation-independent — works in any position
• After firing, remove adapter and tip upside down to eject spent 9mm case
• Made in the USA

Ideal For

• Preppers and Bug Out Bag setups — one gun, two calibers
• Hunters and backcountry shooters looking for compact versatility
• Surprisingly accurate at practical field distances

Note: Designed exclusively for break-open style shotguns. Not recommended for pump-action or semi-automatic shotguns.