The Chiappa X-Caliber Gauge Adapter Insert (brand part no. CF710375) lets a 12 gauge break-open shotgun chamber and fire .40 S&W ammunition, turning a single break-action gun into a multi-caliber tool for small game, pest control, or general utility shooting. Chiappa machines the insert from blued steel with a fully rifled 8-inch bore, which stabilizes the pistol-caliber bullet for genuine accuracy rather than the tumbling pattern a smoothbore insert would produce. It’s built for use with any break-open shotgun and works best paired with a manual extractor recommended for this style of insert. Simply drop it into the chamber, close the action, and the shotgun is ready to fire the adapted caliber.

Key Specifications

• Adapts a 12 gauge break-open shotgun to fire .40 S&W ammunition.
• Measures 8 inches long for a genuine rifled-barrel insert.
• Bore is fully rifled, stabilizing the bullet rather than letting it tumble.
• Machined from blued steel for durability and a traditional finish.
• Fits any break-open shotgun.
• Uses manual extraction rather than an automatic ejector.

Frequently Asked Questions

What shotguns does this fit? Any break-open 12 gauge shotgun; a manual extractor is recommended for this style of insert.

Does the insert stabilize the bullet? Yes, the 8-inch bore is fully rifled rather than smooth.

How does extraction work? This insert uses manual extraction rather than an automatic ejection system.

Find more shotgun adapters and parts in our other shotgun accessories & parts category from Chiappa Firearms.

Buy the Chiappa X-Caliber 12 Gauge to .40 S&W Adapter Insert

One break-open shotgun and a small collection of X-Caliber inserts covers a surprising range of shooting needs without buying a second gun. Order it from our Lubbock, Texas gun shop for fast, direct shipping.