Sig Sauer P320 Compact X-Change Kit .357 Sig - Black (CALX320C357BSS)

The Sig Sauer P320 Compact X-Change Kit in .357 Sig lets you transform your existing P320 Compact into a different caliber platform without buying an entire new pistol. This is the real draw of Sig's modular P320 system: swap the barrel, slide, grip module, and magazine, and you've effectively got a fresh shooter tailored to your ammunition preferences or mission requirements. The .357 Sig is a serious intermediate option—more velocity and energy than 9mm, flatter trajectory than .40 S&W, and a proven performer in both duty and hunting contexts. If you already run a P320 Compact and want to expand your caliber flexibility without the cost and safe-queen clutter of a second gun, this kit is a straightforward way to do it.

Installation is straightforward: field-strip your P320 Compact, install the X-Change components, and reassemble. No gunsmithing required. This modularity is what separates the P320 from single-caliber designs and makes it a practical choice for shooters who reload, hunt multiple game, or simply like having options on the range. The kit ships with a Medium grip frame, which fits the majority of shooters but is worth noting if you're downsizing from a larger P320 or prefer a different ergonomic profile.

One important compatibility note: this X-Change kit does not work with manual safety P320 models—only with the standard P320 Compact platform. If your current gun has a safety lever, you'll need to confirm the receiver is compatible before ordering. Assuming you've got a standard P320 Compact, this .357 Sig kit opens a capable caliber option that balances recoil, ballistics, and ammunition availability in a way many shooters appreciate.

Key Features

• Drop-in barrel and slide assembly in .357 Sig caliber for quick, tool-free conversion
• Includes grip module and magazine sized to Medium—ready to shoot once installed
• Leverages the P320 Compact's proven modular design for genuine versatility
• No gunsmithing or special tools needed for caliber changeover
• Expands your options without requiring a second gun

Specifications

Frequently Asked Questions

Will this X-Change kit work with my P320 Compact with manual safety?

No. This kit is not compatible with manual safety models of the P320. It is designed for the standard P320 Compact platform without a safety lever.

What comes in the box?

The kit includes the barrel and slide assembly in .357 Sig, a Medium grip module, and a magazine. You will use these components to convert your existing P320 Compact.

Do I need special tools to install this kit?

No. Installation involves field-stripping your P320 Compact and reassembling it with the X-Change components. No gunsmithing or specialized tools are required.

What grip frame size does this kit come with?

All Sig Sauer caliber exchange kits are supplied with Medium grip frames, regardless of the caliber or configuration.