The Ruger AR-15 Assembled Upper Receiver (Ruger part no. 91003) is a complete, mil-spec upper built by Ruger / Sturm, Ruger & Co. for drop-in compatibility with standard AR-15 pattern lowers. Finished in matte black, this upper arrives fully assembled and ready to mate with any mil-spec AR-15 lower receiver for a quick build or a second configuration on an existing rifle. It’s a straightforward way to add a dedicated upper without buying a whole new AR-15. Whether you’re building your first AR or adding a spare upper for a different barrel length, this Ruger upper delivers factory fit and finish.

Key Specifications

• Product type: assembled AR-15 upper receiver.
• Finish: matte black.
• Compatibility: mil-spec AR-15 pattern lower receivers.
• Manufacturer: Ruger / Sturm, Ruger & Co..

Frequently Asked Questions

Will this Ruger upper fit any AR-15 lower?
Yes. This assembled Ruger AR-15 upper receiver is built to mil-spec dimensions, so it mounts on any standard mil-spec AR-15 lower receiver.

What finish does this upper come in?
It ships in a durable matte black finish that matches most factory and aftermarket AR-15 lowers.

Buy the Ruger AR-15 Assembled Upper Receiver

This Ruger AR-15 upper, part of our AR15 Uppers lineup, ships fast from our Lubbock, Texas gun shop — order online today.