One Horse 16Inch .300 BLK Complete Upper Receiver with 15Inch M-Lok Free-Float Handguard

Upgrade your rifle with this dependable 16″ .300 BLK complete upper receiver. Built for accuracy and smooth performance, it features a free-float 15″ M-Lok handguard for solid accessory mounting and improved barrel stability. The nitride BCG delivers reliable cycling and low-maintenance durability, while the full-length Picatinny rail gives you plenty of room for optics. Ready to pin onto any Mil-Spec lower, this upper is built in the U.S.A. and ready for work.

Every One Horse rifle and component is made in America with uncompromising standards. We use U.S.-sourced materials, U.S. manufacturing, and strict quality control at every step. No shortcuts, no imported surprises — just dependable parts built by people who take pride in American craftsmanship. When you run One Horse, you’re running gear you can trust every single day.