Proof Research Stainless Steel Barrel, SIG Cross Drop-In, 308 Win, 20" BBL

Proof Research makes their steel barrels in-house with the exact same commitment to quality and repeatability as employ on their carbon fiber barrels. The drilling, rifling, and lapping process is identical to their composite barrels. They start with the same steel as they use in the carbon fiber barrels.  It is a double stress-relieved 416R stainless steel, a pre-hardened chromium stainless steel that was specifically designed by engineers in collaboration with rifle barrel makers to provide the consistent, high quality and durability the firearms industry demands.

• Excellent machinability for gun drilling and reaming, plus exceptional polishability for uniform lapping
• A homogeneous microstructure which responds to heat treatment providing a uniform hardness along the length of the barrel
• An optimum combination of high tensile strength along with requisite toughness to withstand extreme chamber pressures encountered during firing
• Excellent erosion wear characteristics and corrosion resistance

Barrel Length: 20 Inches
Twist Rate: 1:10"
Muzzle Thread: 5/8-24
Weight: 4.13 lbs