In the case of the CVA Paramount LR45 its not just the barrel but the whole package. It is a Modern Bolt action that just happens to use black powder the barrel is threaded to the receiver "The PARAMOUNT™ is CVA’s newest addition to its muzzle-loading rifle family. Unlike any other CVA rifle, this .45 caliber bolt-action gun was developed and designed to handle “super-magnum” propellant charges and thus provides the higher velocities necessary for killing shots at 300 yards and beyond.

Of course, 2200 FPS plus velocities are worth nothing without the accuracy to put those shots where they belong, and for this, like all premium CVA’s, the PARAMOUNT features a custom quality, .45 caliber, free-floating Bergara® barrel in Nitride treated 416 grade stainless steel. Paired with PowerBelt’s new ELR bullets, which were specially designed for the PARAMOUNT, this barrel can produce incredibly tight groups at ranges previously thought unreachable for a muzzleloader.

Also standard with the PARAMOUNT is CVA’s VariFlame® Breech Plug, which uses the hotter and more consistent Large Rifle Primer by utilizing the VariFlame® technology by Cecil Epps, rather than the 209 Shot Shell Primer. For maximum comfort and stability, the PARAMOUNT stock supports the barrel upon an internal aluminum chassis and offers full ergonomic adjustability of both length-of-pull and comb height.

An accessory pack including PowerBelt ELR bullets, VariFlame primer casings, loading tool for VariFlame® casings

I would guess CVA has good reason to bill this as the best of their line. They've tested it and fired it, many times I'm sure. In most cases, the accuracy of any firearm depends on the capabilities of the shooter more than any other factor.

A longer barrel on rifles with iron sights does contribute to much better accuracy because of a longer sight radius. A 26 inch barrel with modern powders and bullets and a scope is plenty long enough.

Daniel, this will depend entirely on the cartridge and powder burn rate. A faster burning powder cartridge can get to the same velocity in a shorter barrel making the longer barrel insignificant or possible detrimental to additional velocity due to friction which can actually produce a slower overall velocity. Barrel length is not the only factor in long range or other shooting scenarios.

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