BJ - Double bet much larger than the initial bet

Hello, lately I've been seeing that at the "Classic Blackjack in Spanish ##" tables there are people who bet, for example, $3,000.

These people, when they get an 11 in their first two cards, at the time of doubling the bet, I see that they can enable a much higher amount, for example 2.5 million. I am interested because despite being much riskier, depending on the card the dealer has, you can win much more money in a single bet.

I add a video of a bet made this way

https://files.fm/u/4v7bzqf5ed

Hi, I would like to start by asking, do you have a question or did you just want to say that this is something you want to try? 

Blackjack and double bet, increase your bet by the amount you bet at the beginning of the round. It is usually recommended to do this when you have 9,10, ideally 11, and of course you have to look at the dealer's cards to make sure you don't double in "risky situations", for example when the dealer's first card is also a 10. Also it is good to know, you can double only after dealer gives you first 2 cards. When you hit and want to double after that, it is not possible.🙂

If you would like to read more about blackjack we have a pretty handy guide for that here- The Ultimate Beginner's Guide to Blackjack.

If you have any more questions or anything else, feel free to let me know.