The only point I have to add is that unlike, say, Roulette, Blackjack rules vary enormously from casino to casino (especially when looking at different cities or countries). I think, then, that the first question is unanswerable, except with respect to a specific casino. The pit boss at the casino you were in will probably be a better authority on the rules at that casino than anybody on this board.
The answer to the second question is no, you shouldn’t double if allowed, as pointed out by others. The only case I can think of that might be worth doubling is if the casino pays straight money for blackjacks. In which case you shouldn’t be playing there anyway.
At the casino i deal at, and every casino in Australia, a Blackjack is an automatic win (unless the dealer is showing an Ace or Ten value card). You can not play this hand, the only thign you can do is take even money if the dealer is showing an Ace (taking even money is the same as taking full insurance, regardless of the result, the payout will be hte same)
Im sure at some Casino’s in the US you can double and what-not on a Blackjack (which is different to a 21) but im very suprised that the dealer didnt know what to do, and that he manager (Supervisor or Pit Manager?) hadn’t heard of it before.
I’m not. It’s a very unlikely thing for a player to do, kinda like saying “I won, but what the heck, I’ll give the house another chance.” The dealer is probably so accustomed to seeing the player has a blackjack, seeing that the dealer himself doesn’t and automatically handing over the winnings that any interruption upsets the whole process.
I guess its just a common sense thing on my part, but if someone said that to me they’d recieve an “Im sorry, you cant do that, its the rules.” Of course in a much nicer tone.
But then again, seeing the quality of some dealers out there im guessing a few would respond with “um um… oh no, thinking for myself… ughhhhhh… SUPERVISOR!”
I’ve actually done this a couple of times. I think there was alcohol involved, and friends and I were joking about what a stupid move that would be… So on my next blackjack, I doubled down. I don’t remember the particulars but the dealer let me do it. This was in Nevada, if that’s relevent.
I’m with Otto. If the rules don’t specifically say that you can’t double down a 21, or that a natural 21 is an automatic win, then doubling is not an option. However, unless you’re really going for broke for some reason (like a tournament), then doubling down on a natural (or any 21) has got to be the worst play out there – even worse than splitting 10’s.
Anecdote: I was sitting at a $5 table at the Sands in AC, and a player attempted to do the same thing - double down on a blackjack. After some discussion, the pit boss getting involved, and a phone call made, they let him do it.
I don’t know about the rules used in AC, but I’m not surprised that the casino was eager to permit such a bone-headed (return-on-investment-wise) play.
Further comment: this kind of silliness is why I hate playing at $5 tables.
Everyone is assuming that BJ pays 1.5. That is usually true, but not always. The most common reason is split aces only get one card, if its a 10 it pays 1:1. You cannot draw or double after that.
Blackjack is a whole family of games with many variations of the rules. you have tocheck the rules for the particular game you are playing. There are variations that pay 1:1 on BJ, but give other advantages instead. For example in Blackjack Switch you play 2 hands at once. BJ pays 1:1, but the ability to swapcards between your hands more thancompensates for this.
So, in a situation like this, or similar, it might be advantagous to double down. If the shoe is extremely 10’s heavy. But in all these cases the rules specifically forbid it.
I have always figured that whether or not you can double-down on a blackjack is (or should be) a house rule. The house would be wise to allow it, as Doctor Who points out with the math. (I love the Wizard.) Anyway, I actually have been asked if I wanted to double-down a blackjack. Apparently people at one casino I got to occasionally have started doing it and throwing a fit if the dealer doesn’t allow them to so I got asked first. My reply of “You’re kidding, right? Who’s stupid enough to do that?” to the dealer got complete agreement and astonishment that people were doing it.
As a side note, in Blackjack Switch the ability to swap cards is compensated in a few ways. One is the blackjack payout. Another is the European no-peek rule and the limitations in how aggressive the player can be in doubling and splitting (though that can actually save you, if say you get a pair of aces in one hand and a pair of tens in the other). At least, the rules as written by the guy who came up with it have the game played no-peek, but it looks like Vegas has changed the rules to put the odds more in their favor. A third is that a dealer 22 is not a win for the player but a push.
I wonder if there’s any BJ variant like this - You can double down on BJ, and if you win you get 3:2 on your increased stake. I’ve never seen it, but I wonder.
Look guys, I’m on a vacation right now and I haven’t been getting much sleep lately. I have no excuse for my reply to frylock, nor can I explain my reasoning. So, Frylock, I do apologize.
Having played and won many blackjack tournaments, i’ve doubled down on the ace a couple of times on the last hand when I was in second place and my bank was first to the first place player’s bank.
If my blackjack wasn’t going to pay quite enough to push me into first place, but winning a double down would give me enough, I did it.
But in a tournament, you’re playing against the other players at the table (the player with the most money after x number of hands wins the tournament).
I don’t know the mathematical odds of doing better by doubling down on blackjack, but I’m pretty sure that casino security would be highly suspicious of you as a card-counter if you did such a thing. (A skilled card counter could tell if the odds were high enough to do such a thing, but then again, a skilled card counter would know better than to attract that kind of attention.)