WW2 Gebirgsjäger Boots - How to soften the leather ?

[AlecH]

Purchased a pair of Gebirgsjäger boots a couple of weeks ago, condition is good, although the leather boot tops are hard and stiff. I intend to rub a coat of dubbin over the boots, leave to soak for a week, then reapply another coat of dubbin and so on until the leather softens. I've never tried this before, thought it best to check it out in case I'm doing anything wrong or perhaps members have better suggestions. Any information welcome.
Regards

[Inf Div 121]

Diggers from Russia use Ballistol oil even on dug out leather, they have very good results with it, sadly I can't by it in Latvia, so I never tryed. ballistol - The World's Most Use-ful & Environmentally Friendly Lubricant