Small cylinder, big hole.
Interesting.
If the cylinder hit on its end, the hole wouldn’t be much bigger than the diameter of the cylinder.
If it hit on its side, the hole would be a slot not much wider or longer than the cylinder itself.
How did it make a round hole bigger than its largest dimension?
Throw a baseball through a window. The hole is much larger than a ball. The stress lines in the sheet rock and the supporting beams are not uniform. The hole is always larger than the object penetrating.