The Cimarron 1866 Yellowboy is a lever-action rifle chambered in .38-40 Win with a 19-inch barrel and a brass receiver. It holds 10 rounds and has a wood stock with a blued finish. 
 

Key Specifications 

• Brand: Cimarron 
• Model: 1866 Yellowboy 
• Caliber: .38-40 Win 
• Action: Lever Action 
• Capacity: 10 rounds 
• Barrel Length: 19 inches 
• Finish: Blued with Brass Receiver 
   

Detailed Features 

• Brass receiver in the 1866 carbine configuration 
• 19-inch barrel with blued finish 
• Wood stock 
• 10-round tubular magazine capacity 
• Chambered in .38-40 Win

Owners of the Cimarron 1866 Yellowboy tend to praise the brass receiver finish, calling it one of the more visually accurate reproductions of the original 1866 pattern available at this price point. The lever action cycles smoothly out of the box for most, though a small number report that a break-in period is needed before the action feels truly slick.

In the field, the 19-inch carbine barrel makes the rifle handy and well-balanced. The .38-40 Win chambering draws a devoted crowd of cowboy-action shooters who appreciate the period-correct cartridge pairing, but sourcing factory ammunition can be a minor inconvenience compared to more common calibers.

Value opinions are generally positive for what the Yellowboy delivers, though some buyers note that the wood stock fit and finish can vary between individual rifles. Aftermarket support for the 1866 pattern is narrower than for the 1873, which matters to owners who want to customize or tune their rifle.