reflects a railing to knock a guy back

He immediately tried to stick out his fist, but Accelerator’s foot struck the ground first.
The steel rail lying at his feet stood up as if a spring lay beneath it. The bolt in the
railroad tie popped off like a shirt button.

Before Kamijou could respond in surprise, the rising rail struck him in the chin like an
uppercut.
“Ghah...!”
His body shot up and a space of twenty centimeters opened up between his feet and the
ground. Accelerator watched that with a satisfied look and opened up his right hand like
it was a demon’s claw and aimed it for Kamijou’s airborne body.

- Toaru Majutsu no Index Volume 3, Chapter 4 Part 6