Doubling down on 20

Quote: noy2222

I propose naming this side bet "Stupid Motherf$$ker".
It costs a dollar per round and pays off when you double and win on a natural 20 or a natural 6.

Casino 5 card poker could claim that title. odds of getting a flush are 1 in 508. Can the player's odds doubling on hard 20 on BJ be worse than this?

Quote: piroukay

Casino 5 card poker could claim that title. odds of getting a flush are 1 in 508. Can the player's odds doubling on hard 20 on BJ be worse than this?

Kind of apples-to-oranges comparison, right?

Unless..

96/312 x 95/311 chance of getting a hard 20 in the first place, x 24/310 chance of then getting an ace, for 6 deck. 1 in 137.4267 hands is what I get, apples to apples.

But once you already HAVE 2 tens (6 deck), you have a 7.742% chance of getting an ace to go with it, or 1 in 12.99 hands. Which I would think you knew (1 in 13 cards being an ace).

It could be a free bet.

If a player has a 20, offer to pay some multiple of his existing wager if he hits and gets an ace.

If he busts, he just loses his existing wager.

As a free bet, and with a sufficiently high multiplier, you could get lots of suckers to fall for it while maintaining an obnoxiously high house advantage.

Is it 1 in 13 still with six decks?

At the point of possibly hitting a hard 20, the odds of an ace are not exactly 1 in 13, because the only two known cards already in play are both 10-vale cards; i.e., non-Aces. (Or rather at least two non-Ace cards totalling 20? I suppose your hard 20 could include an Ace, but I haven't been thinking of the problem that way.) I think that should make the odds very slightly higher than 1 in 13, perhaps the 1 in 12.99 suggested by BBB (if I am remembering her post correctly without looking back.)

It sounds like a waste of space to me. Someone has a good hand and they want to pay extra to destroy it, I don't think so. Sounds like it would slow down the game. There are better ideas than this to investigate.

Seems Iike this would appeal to someone that plays blackjack like poker. i.e. If they can't raise they fold. There is maybe a few players out there that want to and will double everything. Saw one regularly in the Cannery couple years ago. I think he hated money.😳

Assuming a fresh shuffle and the only exposed cards are 2 ten-value cards and the dealer's upcard (which we'll assume is not an ace), there are 24 Aces and 285 non-Ace cards unseen in a 6-deck shoe. So, odds for an Ace = 24 in 309, or 1 in 12.88.

Further, if the dealer's upcard is an Ace (or if your 20 consists of A-9), then your odds would be 1 in 13.43. And if you had A-9, and the dealer also had an Ace, the odds would be 1 in 14.05.

Of course, the odds will change with each card dealt. I'm no counter, but I would think this type of bet would be easily vulnerable to someone just counting aces.

The only way you can make a 2-card hard 20 is with two 10-value cards. Since most casinos do not allow doubling on 3+ cards there are no other possible combinations for this scenario under normal rules (and A+9 is a soft 20, which although still a bad play to double is much safer than doubling on a hard 20).

Thank you, everybody, for all your help, guidance and amusement.