Convert from pes to caliber

Unit Definition (pes)
The pes is the Roman foot, equal to 29.67 centimeters (about 11.68 inches). The pes was divided into 12 unciae (inches). There were 5 pes (or pedes) in 1 passus (pace, see above), 10 in a decempeda, 625 in a stadium, and 5000 in the Roman mile.

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."