9 X 18 Ultra is not the same thing as 9 X 18 Makarov. The ammo is hard to find. I have never seen any. It was designed to up the power of the Walther PP/PPK series of guns (they cannot handle the 9mm Luger).
I believe it is essentially a lengthened .380 case (1 mm). You can probably load it using .380 dies (but not 9mm Luger dies)
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