Proof Research's patented manufacturing process begins with full-profile, match-grade 416R stainless steel barrel blanks that are made in their firearms division.  These blanks are then turned down to a significantly reduced profile greatly reducing weight. This reduced contour barrel is then wrapped with high-strength, aerospace-grade carbon fiber impregnated with a proprietary matrix resin developed by their advanced composites division, PROOF Research ACD. The aerospace-grade carbon fiber used has a specific strength up to 30 times that of stainless steel and a specific stiffness up to 7 times greater than steel. Strength and stiffness are only part of the equation. Heat conductivity and thermal expansion are also of paramount importance when developing a match-grade carbon fiber barrel. The helical wrapping pattern favors the longitudinal thermal diffusivity of the carbon fibers (along the length of the barrel) allowing them to more efficiently dissipate heat emanating from the barrel rather than insulating it. Because Proof Research rifle barrels are engineered for thermal performance, they also move heat very effectively through the wall (thickness) of the barrel, greatly increasing heat transport and resulting in barrels that cool faster and maintain accuracy over longer sessions of fire. The end result is an aerospace-grade, high-fiber content composite barrel that is stronger, lighter, as accurate as the finest precision steel barrel, and maintains its accuracy in the most demanding environments. THE ONLY CARBON FIBER-WRAPPED RIFLE BARREL APPROVED FOR USE BY THE U.S. MILITARY.

• Proof Research Premium Match Grade Barrel
• Carbon fiber wrapped stainless steel-Up to 64% lighter than traditional steel barrels of similar contour
• .338 caliber : suitable for cartridges .338 Win Mag, .338 RUM, .338 Lapua, .340 Weatherby, etc.
• 5 groove rifling
• Extreme Temperature Resistance - Improved heat dissipation for cooler and longer lasting barrels
• No point-of-impact shift during high-volume fire
• Unprecedented durability - Wrapped with high-strength, aerospace-grade carbon fiber impregnated with a proprietary matrix resin.
• This barrel must be chambered, threaded, crowned and installed by a certified Gunsmith  

WEIGHT:
24" - 3lbs 6oz
26" - 3lbs 9ozs

SENDERO CONTOUR

Measurement	Length/Distance	Diameter
A	3.00"	1.250" (Shank Diameter)
B	3.69"	1.250"
C	6.00"	1.113"
D	10"	1.073"
E	Barrel Finish Length	24" - 0.939" 26" - 0.919"
F	.800"	Dependent on Barrel Finish Length
G	To be Removed by Gunsmith	0.625" (.25° Draft)

*Diameter at 10" is to aid in determining fitment in a stock's barrel channel by representing a typical distance from the breech face to the end of the forearm.