A practical solution, and if it pleases the owner so be it.

I would have been inclined to modify a few cases instead of the rifle.

I've been following this with the question about why this caliber was created in the first place.

Is it because no self respecting Austrian would build a rifle for a British caliber?

Is it to prevent the .450 from being chambered due to load/pressure differences? Or bullet weight/type?

Was it to comply with some kind of legislation?

Perhaps to control ammunition supply to the maker or country?

Is this lost to history someplace or does anyone know?

"The price of good shotgunnery is constant practice" - Fred Kimble