I know they make a KX-5 with a left handed stock my friend just bought one LH palm swell and definately cast left handed and has a krieghoff pad so I think it's original.He was wondering if the barrels are backbored stock or if someone did his the bore on his is is .750.Jerry
Every standard factory Krieghoff trap stock I've ever owned (nine of them) or seen has been neutral with an ambidextrious palm swell. However, at the 2005 Grand, I was at Wenig's having a stock fitting when Dieter Krieghoff met with Delbert Smith, Fred Wenig's partner at the time. At the conclusion of the meeting, Dieter and someone with him left with armloads of Wenig New American stocks. They are left- or right-handed, so they would have a "one-sided" palm swell.
Perhaps your friend got one of those stocks or his gun's stock was replaced along the way. The latter is a good possibility as the bore was altered, too - every recent Krieghoff barrel I've run my bore micrometer through has measured .730" within a half-thousandths.