How does a gut wound smell and look?

Depends on if the bowel was perforated, but even then it won't smell very nice. Lots of blood if the abdominal aorta or inferior vena cava have been hit. The guts themselves would look like wet, knotty rope, whitish in color.

If the bowel or stomach are punctured then it's gonna be vile. Bowel wounds are bad, they smell like every toilet you've ever been in. Litterally rotting.

Take some broccoli, steam it, then put it in the back of your fridge for about a month,maybe longer- take it out, pull off the top of the container- Yeah- like that only worse.

What it looks like greatly depends on where and how penatrating.

Intestines don't spill out of the living or recently deceased. They are attached by the mesenteric blood vessels all along their length. They might be visible if there is a large enough wound and you'd be able to see them peristalse, which is mesmerizing the first time you see it. The smell is not like anything rotting (assuming this is a fresh wound). It smells bloody and to most modern people this is an unfamiliar smell and unpleasant. The first time you scrub on an abdominal case it is gripping in its intensity but you get used to it pretty quickly unless you don't and then you don't stay in surgery. If the bowel is perforated then there will obviously also be the smell of flatus and feces.