The CMMG AR-15 front sight base assembly is a purpose-built front sight and gas block unit designed for AR-15 platforms running .750" gas journals. If you're building or upgrading a mid-length or rifle-length AR, this assembly gives you a solid, integrated solution that combines your front sight post with a functional sling loop attachment point. It's the kind of component that lives at the heart of a reliable, no-frills combat or hunting rifle.

This is a gunsmith-level installation job—you'll need proper tools and expertise to seat it correctly on your upper receiver. We'd recommend having a licensed gunsmith handle the fitment and headspacing to ensure everything functions as it should. Note that taper pins are sold separately, so factor those into your build if you don't already have them on hand.

Whether you're assembling a new upper from scratch or refreshing an existing rifle with a fresh gas block and front sight solution, the CMMG assembly offers the kind of straightforward, proven design that shooters have relied on for decades. Pair it with quality furniture and a reliable bolt carrier group, and you've got the foundation of a rifle that'll work when you need it.

Key Features

• Integrated front sight post and sling loop attachment
• Sized for .750" gas journals (mid-length and rifle-length AR platforms)
• Gunsmith installation recommended
• Taper pins required but not included

Specifications

Gas Journal Diameter	.750"
Includes	Front sight post, sling loop
Installation	Gunsmith recommended
Taper Pins	Not included

Frequently Asked Questions

Does this front sight assembly fit my AR-15?

The CMMG assembly is designed for AR-15 platforms with .750" gas journals, which are standard on mid-length and rifle-length builds. Check your gas journal diameter before ordering. If you're unsure, measure or contact a gunsmith to confirm compatibility.

Can I install this myself?

This is a gunsmith-level component installation. Proper seating and alignment require specialized tools and experience. We recommend having a licensed gunsmith handle the installation to ensure correct fitment and function.

What else do I need to complete the installation?

You'll need taper pins to secure the assembly, which are not included with this product. Order those separately. Your gunsmith may source them as part of the installation job.

Does it come with a sling attachment?

Yes, the assembly includes a sling loop for mounting sling hardware, giving you a complete front-end solution.