Christer:

Nitro is right, if you go with the Krieghoff or the Merkel, you had best budget for tearing off the sights and starting over. The Merkel comes with a flattop U-notch rear and a square post up front as does the Krieghoff in calibers up to .375. These are as bad as nitro describes. The larger caliber Krieghoffs come with a wide-vee rear with a white plastic insert and a large brass bead up front. These are too coarse for adequate precision at 50 yards, much less 100, and suffer badly from glare.

Christer, since the ballistics of the .500/.416 seem acceptable to you, and you intend to handload, why not get a nice second-hand English boxlock in .450/.400 for the same money? Or, for a bit more money (and .470 horsepower), a .450, .500/.450 or 450 No. 2? Better rifles and money better spent.
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