If the bolt hole in the wedge extends all the way through the barrel nut to the other side of the eccentric like on Cannondales, then a another method works well. I recommend this as I've heard of the (rather long) eccentric bolts being bent by the forces of hammering on them.
Unscrew the eccentric bolt to the point where it's just about to unthread from the barrel nut. Screw in a shorter bolt from the other side - once it threads, remove the long eccentric bolt. (this prevents the barrel nut from moving, which would make things rather bad - you may not get the hole in the nut to line up with the bolt again!) The screw from the other side should be threaded through a backing plate (the hole in a headset wrench or cone wrench works great). With a few washers and lube, screwing the bolt into the wedge from the other end will pull it free as the backing plate bottoms out on the BB shell and/or eccentric. I carry an extra long water bottle bolt & cone wrench on trips so I can adjust timing chain tension anywhere. No need for a hammer and brute force!