Any non angle lock vice will nearly always cause stock to lift, as the moving jaw will lift up when tightening.

If it's a high enough bit of stock, put a bit round bar between the moving jaw and the work piece, snug it up, then give the material a tap down with a hammer (ideally made from something softer than the material you're hitting, unless you're not worried about leaving marks) to make sure the materials seated against the base.

But as per Jazz's post, I love my Gerardi vice from Cutwel, but they're probably a touch expensive (even when on offer!) for hobby use.