The Sig Sauer MCX Spear-LT is a semi-automatic pistol chambered in .300 AAC Blackout with a 9-inch barrel. Overall length is 18.8 inches. Weight is 5.6 lbs (2.5 kg). Capacity is 30+1 rounds. Finish is Coyote Tan anodized. No sights included; the platform is optic-ready. 
 

Key Specifications 

• SKU: PMCX-300B-9B-LT 
• UPC: 798681660841 
• Caliber: .300 AAC Blackout 
• Capacity: 30+1 rounds 
• Barrel Length: 9 inches 
• Overall Length: 18.8 inches 
• Weight: 5.6 lbs (2.5 kg) 
• Action Type: Semi-Automatic 
• Finish Color: Coyote Tan (Anodized) 
• Sights: None, Optic Ready 
   

Detailed Features 

• SIG Flatblade Match trigger 
• Fully ambidextrous controls 
• Interchangeable barrel system 
• SIG QD suppressor-ready flash hider 
• Lightweight ergonomic handguard 
   
  The 9-inch barrel in .300 BLK is a suppressor-optimized configuration -- the cartridge was designed for short barrels, and subsonic loads work well through a can on this platform. The interchangeable barrel system lets owners swap lengths or calibers without a gunsmith. The SIG QD flash hider accepts SIG's quick-detach suppressor interface. No iron sights are included, so buyers need to budget for an optic.

The Sig Sauer MCX Spear-LT in .300 BLK Coyote Tan draws comments primarily from suppressor users and .300 BLK enthusiasts.

Build quality is consistently praised -- the MCX platform has a strong reputation and the Spear-LT inherits that. The Coyote Tan anodized finish gets positive comments for appearance and field utility. The ambidextrous controls work well for left- and right-handed users.

The .300 BLK caliber's versatility is frequently discussed. Users note the ability to run both supersonic hunting loads and subsonic suppressed loads from the same platform as a key advantage. The SIG QD suppressor interface is noted as a clean implementation for NFA owners who already run SIG suppressors.

Weight and size discussions are nuanced -- at 5.6 lbs with an 18.8-inch overall length, it's compact for the barrel length, but some users note it feels less nimble than shorter pistol configurations when loaded and accessorized. Price is at the upper end of the .300 BLK pistol market, and most discussions accept this given the MCX platform quality. The lack of included sights means buyers need to factor in the cost of an optic.