For the most part, accuaracy can be had with short or long barrels. Velocities though will be slightly slower with the shorter tubes ie. Ruger Compact with a 16" barrel vs say a rifle with a conventional 22" barrel. The caliber in question also matters, the 270, 243, 308 etc will burn all the powder efficiently in a 22" barrel while the belted magnums(using more powder, also slower burning ) need longer barrels ie. 26" for a complete burn.

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