How to make hand stop at the wall when punching? (Weird fast stretching/rotations)

I'm trying to get a boxer to punch at a wall, and it has been very difficult to make it not go through the wall. I have used Dogzer's 'Inverse Kinematic' such that I can move my arm around. When I try to drag it through a wall , it looks like it stops, but at the same time it totally messes up.

It looks sort of okay up until the point where it touches the wall, but when it touches it goes berzerk. It spins around, moves around, stretches the mesh etc. extremely fast. Almost like it continuously both want to go through the wall and stay in front of the wall at the same time. I can see that my colliders/rigidbodies etc. in my arm are not holding together at all while it happens.

How can I make the hand stop at the wall without all these weird movements?