Blackout looks sufficiently stunned afterwards. Blackout is disintegrating his body, but rather than panic or scream, he merely delivers a 'Facing the Bullets' One-Liner and then headbutts Blackout so hard that his own head smashes apart. Moreau's Dying Moment of Awesome near the end of the film.
Made even more fearsome because actual bucketwheel excavators are glacially slow, and moving at even a fraction of the speed it does in that scene would make it disintegrate from the forces exerted upon its frame. Perfectly reasonable for it to be in a quarry where arms dealers meet. You know that picture of a giant saw-bladed monstrosity ◊ that's been making its rounds on the internet? That's a coal mining machine.' Sorry, does it hurt? Looks like it does.'