How To Mount A Scope On An AR

Learn how to properly mount a scope on an AR-15 with this beginner-friendly Brownells Tech Tip. Caleb walks through the complete process of mounting and leveling an LPVO optic using a cantilever scope mount, including proper eye relief setup, torque specs, scope leveling techniques, and common mistakes to avoid. Whether you just bought your first AR-15 or you're upgrading your rifle with a new optic, this guide covers everything you need to confidently install your scope the right way. In this video, we cover why AR-15 rifles require cantilever mounts, how to avoid bridging the receiver and handguard, proper ring placement, how to level your optic correctly using an Arisaka scope leveling tool, and how to bore sight your rifle before heading to the range. Caleb also explains torque specifications, scope ring alignment, and how improper mounting can affect accuracy. Chapters: 00:00 Introduction 00:30 AR-15 Setup and Front Sight Considerations 01:03 Choosing the Right Scope and Mount 01:59 Why Cantilever Mounts Matter 03:30 Scope Ring Sizes and Mount Compatibility 04:07 Setting Eye Relief 05:55 Securing the Rifle in a Vise 06:18 Mount Installation and Torque Specs 08:25 Installing the Scope in the Rings 10:02 Proper Ring Placement 10:57 Equalizing Ring Gaps 12:44 Why Scope Leveling Matters 13:46 Common Scope Leveling Mistakes 14:52 Using the Arisaka Scope Leveler 17:13 Tightening and Torquing Ring Screws 19:49 Final Scope Alignment Check 20:10 Bore Sighting an AR-15 21:45 Final Thoughts Products Featured: Sig Tango MSR 1-4x LPVO AR-15 Cantilever Scope Mount Fix It Sticks Torque Driver Arisaka Scope Leveler Brownells AR-15 Vise Block Mounting a scope on an AR-15 the right way is critical for accuracy, reliability, and comfort behind the rifle. This video explains proper optic mounting techniques for LPVOs, red dots with magnifiers, and traditional rifle scopes on AR-platform rifles.