Let me start by saying I've only played in a casino a few times in my life so I'm not sure if this would be kosher.

If a pot goes heads up and my opponent makes a bet on the river can I flip my hand while I'm deciding to call to guage a reaction?

This could be an FAQ. The result will vary from room to room.

In a cash game, in most casinos, yes, you can do this. But be sure to find out before you try it; some rooms are rumored to automatically kill your hand if you do this (never played in one myself). If you are in a place that allows it, you should be pretty upfront about what you're doing so you don't confuse the dealer into mucking your cards, or your opponent into thinking you've folded. Just state something like "I'm not folding, yet" as you turn over your cards and you'll save everybody some occasional aggravation.

However, in a tournament in pretty much any casino, you cannot do this. The penalty for doing it varies from being told not to do it again, to being told to sit out one round, or so, to having your hand killed. Never do this in a tourney.

I'll be sure to ask.. Thanks for the advice bav..

Oh I hope I actually get someone to try this with me.. I'll sit there GRINNING like a damn idiot so the person thinks I'm strong..

At Commerce you have to act within 10 seconds of exposing your hand or they are supposed to muck it.

OP, what are you hoping to get out of this? You said you've only played in a casino a few times. Can you tell the difference between a bad acting job, a good acting job, or a genuine reaction? I can tell you that of all the times I've seen someone try this, 95% of players, even really bad players, have no reaction at all.

In tournaments it is a rule that you can not show your hand or say what you have but in live games it is not a rule. But I have seen in some Florida casinos they play cash games with tournamnet rules, so as bav says, you better ask what the house rule is before you kill your hand.

you can get around casino rules by just saying what you have, and keep your cards face down...

I've done this in my home game before when I had to make a huge decision for all this guys money. I feel I'm pretty good at reading that genuine 10 msecs.. before the acting can kick in.. Once the initial reaction was to turn beet red and there's no acting job that can stop them from doing it.

Not saying this will work on regulars. I just think alot of people that I come across are just gonna be there for the weekend playing loose and making big bluffs... They aren't used to loosing a few hundred on a hand.. If I flip over a good hand, who knows, they might just get sick.. (this works better when the opponent actually thinks his hand is good)

You are going to give yourself more to worry/think about than u need to

don't do it, don't show ur cards. . .