Convert from caliber to arsheen [Russia]

Unit Definition (caliber)
The caliber is a unit used to express the bore diameter of a gun. Traditionally, the diameter is stated in inches, so that ".22 caliber" refers to a pistol having a bore of 0.22 inches (5.588 mm). So the caliber is actually equivalent to the inch. The usage of the term "caliber" is actually now in decline, because bore diameters of many guns are now stated in millimeters. "Caliber" is the American spelling; elsewhere the unit is often spelled "calibre."

Unit Definition (arsheen [Russia])
The Arsheen, also called the Archin, Archine, Archinne, Arschine and Arshin. In the early 18th century, the Tsar Peter the Great issued a ukase redefining the traditional Russian units of length in terms of the English foot. The archin was made equal to 28 English inches, 71.12 centimeters or 16 Vershki.