Proof Research 6CM 20" Bolt Action Barrel - 7.5 Twist, 5 Groove, Stainless Steel (Model 134573)

The Proof Research 6CM 20" bolt action barrel delivers precision and durability for long-range shooters building or upgrading a rifle in 6mm Creedmoor. This stainless steel barrel features a 7.5 twist rate optimized for the 6CM cartridge, paired with 5-groove rifling and a 5/8"-24 tpi threaded muzzle—standard connections for suppressors and brakes. Built with a drop-in design, it's engineered to function as a direct replacement on Sig Cross platforms, making it an accessible upgrade path for shooters who already run that action.

Proof Research barrels are known for consistent accuracy and reliable performance in demanding conditions. The 20-inch tube strikes a practical balance for 6CM hunting and precision rifle work—long enough to realize the cartridge's velocity and ballistic potential, compact enough to handle in the field or from the bench. Stainless construction resists corrosion and requires minimal maintenance, a real advantage if you're working in variable weather or don't want to baby your gear.

Whether you're chasing long-range accuracy, upgrading an existing rifle, or assembling a purpose-built platform, a quality barrel from Proof Research is a foundation-level investment that pays dividends downrange. The 6CM itself has proven popular among precision rifle competitors and long-range hunters—a superb flat-shooting, low-recoil option with excellent ballistic efficiency—and this barrel gives you the hardware to unlock its potential.

Key Features

• 7.5 twist rate optimized for 6mm Creedmoor performance
• 5-groove rifling for consistent accuracy
• Stainless steel construction for durability and corrosion resistance
• 5/8"-24 tpi threaded muzzle (suppressor and muzzle brake ready)
• Drop-in design compatible with Sig Cross bolt actions
• 20" barrel length for practical field handling and velocity

Specifications

Frequently Asked Questions

Is this barrel compatible with Sig Cross rifles?

Yes. This Proof Research barrel is a drop-in design specifically engineered for Sig Cross bolt action platforms, making installation straightforward if you're upgrading an existing rifle.

What muzzle devices can I mount on this barrel?

The barrel features a 5/8"-24 tpi threaded muzzle, which accepts standard suppressors, muzzle brakes, and flash hiders in that thread pattern—an industry-common specification.

What is the 7.5 twist rate best for?

The 1:7.5" twist is optimized for 6mm Creedmoor performance. This twist rate stabilizes the range of bullet weights commonly used in 6CM hunting and precision rifle work.

Why stainless steel?

Stainless steel resists corrosion and requires less maintenance than chrome-moly, making it ideal if you shoot in wet or variable conditions or prefer a low-maintenance barrel.