Wolf Ammo
The biggest problem with Wolf's ammo is that the casing itself is steel, so when, especially in a semi-auto weapon, the round is fed through, the extractor is beat up quite a bit due to steel-against-steel strikes. Training at a weapons course, I've seen someone use Wolf ammo and get their extractor damaged due to it, rendering their Kimber Custom II useless.
In a bolt-action application, where the feed is a lot more gentle and controlled, there are pobably other issues at hand - like reliability, ballistic properties of the rounds, et cetera, though we don't go through hundreds of rounds through a bolt-action, which make the point a bit moot.
A notable exception to Wolf's ammo tendency to use steel is their shotgun rounds - there they use brass.
My $.02