Conversion Kits for The P320 and P365 | SIG SAUER

Published on May 15, 2026
Duration: 1:51

This guide details the installation of SIG Sauer's CALX kits for the P320 and P365 pistols, transforming them into highly modular firearms. The process involves safely disassembling the firearm, removing the Fire Control Unit (FCU), installing it into a new TXG grip module, and reassembling with a new slide. Specific steps for both P320 and P365 models are covered, emphasizing safety throughout.

Quick Summary

To install a SIG Sauer CALX kit, first ensure your P320 or P365 is unloaded via a three-point safety check. Remove the slide and takedown lever, then extract the FCU. Install the FCU into the new TXG grip module by aligning and pressing the trigger guard, then reassemble the slide and takedown lever.

Chapters

  1. 00:06Introduction to CALX Kits
  2. 00:15Firearm Safety Check
  3. 00:23Slide and Takedown Lever Removal
  4. 00:37FCU Removal
  5. 00:40TXG Grip Module Installation
  6. 01:12Takedown Lever Reinstallation
  7. 01:23Slide Reinstallation
  8. 01:43P365 Specific Pin Removal

Frequently Asked Questions

How do I safely start the CALX kit installation on a SIG P320 or P365?

Begin by ensuring the firearm is unloaded. Lock the slide to the rear, remove the magazine, and conduct a thorough three-point safety check to confirm it is safe to work on before proceeding with any disassembly.

What is the purpose of the TXG grip module in a SIG CALX kit?

The TXG grip module is a new grip modification option included in SIG Sauer's CALX kits. It allows users to customize the feel and ergonomics of their P320 or P365 by providing a different grip platform for the Fire Control Unit (FCU).

What are the key steps to installing the FCU into the new grip module?

Start from the rear of the FCU and the grip module. Carefully work the trigger into the trigger guard, applying both rearward and downward pressure. You can safely press the trigger to ensure the FCU is fully seated within the grip module.

Are there any differences in CALX kit installation between the P320 and P365?

Yes, for the P365, you must first remove an additional pin located at the rear of the grip module using a punch. This is in addition to removing the standard takedown lever before you can remove the FCU.

Related News

All News →

More Gunsmithing & DIY Videos You Might Like

More from SIG SAUER, Inc

View all →