Columbia 23-T sailboat with interesting hole in floor

[brittj007]

Here are photos: http://imgur.com/a/Fh9g0

I just gutted this old boat, and after pulling up the plywood floor, found this hole as seen in photos (along with a good amount of water).

Here is all the boat info I could find:
http://sailboatdata.com/viewrecord.asp?class_id=209
and
http://www.columbia-yachts.com/23-73.jpg

I am wondering what this hole could be. It looks like the ballast only lines the bottom of the keel (which is a ways from the hole), so a keel bolt doesn't seem likely. When I rock the boat, I can see it move back and forth.

Wondering if anyone has ideas, or maybe has knowledge about this boat's inners.

Thanks!

 

[Scott Danforth]

Looks like a shotgun blast. Was the boat a salvage recovery?

 

[brittj007]

Nope, the owner sailed it until it was repo'd. Shotgun not included with boat unfortunately.