CMMG 10-Round Extension for FN 5.7x28mm – Fits 20-Round Magazines

The CMMG 10-Round Extension converts standard 20-round FN 5.7x28mm magazines into 30-round capacity magazines, providing extended firepower for compatible CMMG AR-15 platform firearms chambered in 5.7x28mm. This extension is designed for shooters who want increased magazine capacity without purchasing entirely new magazines, making it a cost-effective solution for range sessions and competition use.

Constructed from durable polymer to match CMMG's factory magazine materials, this extension installs directly onto existing 20-round FN 5.7x28mm magazines. Installation requires disassembly of the magazine base plate and installation of the extension body—basic mechanical aptitude and proper tools are recommended. The extension maintains reliable feeding characteristics while adding minimal weight to the magazine.

• Part Type: Magazine Extension
• Compatible Firearms: CMMG AR-15 platform firearms chambered in FN 5.7x28mm
• Compatible Magazines: 20-round FN 5.7x28mm magazines
• Capacity Increase: +10 rounds (20rd to 30rd total)
• Material: Polymer
• Installation: User-installable with basic tools; magazine disassembly required
• Includes: Extension body and necessary components