I think I've heard of people 'milking' the stomach of a bass in order to find out what they've been eating.  

Any tips for this?

Burley, I have had bass empty the contents of their stomachs in my live well at times. But never heard of milking a bass' stomach to check the contents for possible tells of what they are biting on.

I would think, unless you knew exactly what you were doing, you stood a good chance of injuring the fish handling them. Not worth it IMPO.

Tight Lines!!!

I've heard of it, I think in the case I saw the guy made some kind of homemade stomach pump, don't remember how though.

How to kill a fish part two. Feed them a bunch of candy until they have a tummy ache.