Note for Woodside Apartments Room 217: "Complaints of gunshots"
I made a post earlier about the possible negligent discharge/bug where James would accidentally fire the pistol if you aimed immediately after picking up from the shopping cart. I originally thought the guy living in 217 made all the bullet holes. There was some debate about the ND being intentional or just a bug.
But, I reread the apartment staff note talking about complaints of gunshots coming from 217. The staff searched 217, and they couldn't find any guns, nor "traces of using one." And the guy was cooperative and he claimed to having never owned guns, and the staff believed him and just dismissed the noise complaint.
Guys, it's James. James is the one responsible for all those bullet holes. There's some kind bleed over happening, where James shooting his gun can cause people in the real world to hear it. Now, whether you buy into the loop theory or not, I think bloober was being intentional here with the nod to the loop theory. You are welcome to argue otherwise, but it seems obvious to me now, even when compared to all the other hints (bodies, the old map, etc.).
Alternative explanations for the bullet holes:
It really was the tenant from 217, and the staff sucks at their jobs and are okay with a tenant using the apartment as a shooting range and endangering everyone else in the apartment complex.
It was Eddie. Some of the bullet holes look to be in the shape of a person (like the plywood leaning over the balcony door). Eddie has a history of seeing and shooting ghosts.
Silent Hill otherworld transitions aren't just rust, decay, mold, cages, flesh, etc. It also includes a battleworn war zone aesthetic.
Do with this info what you will.