PROOF Research Sendero Carbon Fiber Bolt-Action Blank 26" .264 Bore

The Sendero contour in .264 / 6.5mm bore at 26 inches is the canonical PROOF Research bolt-action blank for a custom long-range build. Sendero is a heavy tactical sporter contour, not a pure varmint or pure bull profile, so it balances stiffness for accuracy with manageable rifle weight. The carbon fiber wrap over a 416R stainless match liner is what makes it different from every steel competitor: PROOF claims up to 64% weight reduction versus steel for the same external dimensions, and in practice a Sendero CF in this configuration lands in the 2.5 to 3 pound range where a comparable steel sporter is closer to 5 pounds.

Because PROOF sells this as a blank with a .264 bore rather than a pre-chambered cartridge SKU, the same barrel becomes a 6.5 Creedmoor, 6.5 PRC, .264 Win Mag, .260 Remington, or 6.5x55 rifle depending on what reamer the gunsmith spins. Twenty-six inches at 1:8 twist is the right combination for modern heavy 6.5mm match projectiles, including 140-grain Berger Hybrids, 144-grain LRX, and 147-grain ELD-M. Different retailers title the same SKU differently (OpticsPlanet lists it as ".264," Classic Firearms as ".264 Win Mag"); the underlying product is identical.

This is a blank, not a pre-fit. A gunsmith does the chamber, threading, crowning, and final length, so plan on $400 to $700 in additional labor depending on the smith and the work scope. The trade-off versus a Tikka, Defiance, or Zermatt pre-fit is total cost and lead time, but the upside is full custom specification: chamber reamer choice, throat length, muzzle thread spec, and any contour adjustments the smith can manage. For a Rem 700 footprint action specifically, the blank is the right call; PROOF does not sell a universal Rem 700 pre-fit because factory Rem 700 tolerance variance makes universal pre-fits unreliable.