The Cimarron 1866 Yellowboy is a lever-action sporting rifle chambered in .38-40 Winchester with a 24-inch barrel and a 12-round capacity. It has a brass receiver, a walnut wood stock, and a blued metal finish. 
 

Key Specifications 

• Brand: Cimarron 
• Model: 1866 Yellowboy 
• Caliber: .38-40 Win 
• Action: Lever Action 
• Capacity: 12 rounds 
• Barrel Length: 24 in 
• Color/Finish: Blued 
   

Detailed Features 

• Brass receiver, a hallmark of the 1866 pattern 
• 24-inch blued barrel 
• 12-round tubular magazine 
• Walnut wood stock 
• Chambered in .38-40 Winchester

Owners of the Cimarron 1866 Yellowboy typically buy it for Cowboy Action Shooting or as a period-style display piece, and the brass receiver is the most consistently praised feature. The contrast between the brass and the blued barrel is considered attractive, and walnut wood quality is generally described as good for the category.

The lever action cycles smoothly for most buyers from the start. The 24-inch barrel gives good balance for a full-length sporting configuration, and the 12-round capacity is competitive with other 1866 reproductions. A minority report that the action benefits from a professional slick-up job before competition use.

The .38-40 Win chambering is a niche choice. Owners who handload tend to be very satisfied, as factory ammunition in this caliber is limited and often pricier than more common cowboy-action cartridges. Those who don't reload may find sourcing ammunition an ongoing consideration.