Double barrelling is something that is butchered by a lot of regs in the micro-stakes games ($0.01/$0.02 up to $0.10/$0.25). To “double barrel” literally means to bluff two consecutive streets, i.e. by continuation betting the flop and than betting again on the turn.
Double barrelling is actually something that I think needs to be stressed more in online poker. Too many players will make a cheap continuation bet, expect to win the pot there and then, but than if they get called they melt down and feel like they’ve lost all control in the pot.
By double barrelling the turn however you take back control in the pot and whip your opponent into shape. The main problem that I see with cbetting pots is that you’re always going to get called by marginal hands such as draws, mid-pair, Ax, Kx, pocket pairs and overcards on board such as 5-9-Q. These cards still have lots of equity and implied value which is why opponents will call cbets a lot with them (especially against players with a high cbet% of 60% + (you can check these by looking at Poker HUD Stats).
Hence, by double barrelling the turn you eventually make it too expensive for these types of opponents to carry on calling you. Unless a hand like Ax or over cards improve on the turn they will not be able to afford calling another raise. It would be negative EV for them to do so. They will also be too scared to call your double barrel on a missed board because they know that if you raise again on the river and they miss then they will effectively be forced to fold and hand over all of those chips.
What are the Best Cards to Double Barrel?
Obviously you cannot just expect to double barrel every card that is thrown to you on the river since there will be bad, good and excellent times to do so depending on the flop texture and circumstances.
But let’s say the next card on the turn is an Ace. This massively reduces his pot equity in the hand since his mid-pair is now reduced to 3rd pair and his King is beaten by the Ace. Hence, our opponent is a lot less likely to call a consecutive bet on the turn especially now that the stakes are so high.
The second best card to double barrel on the turn are cards that are higher than mid-pair. This is because the majority of your opponent’s calling range on the flop will be 9x/Ax or below. A higher card on the turn such as a K or A still reduces his equity and makes it harder for him to continue playing.
What are the Worst Cards to Double Barrel?
The worst types of cards to double barrel in Texas Holdem are those that hit your opponent’s pre-flop and flop calling range. Cards that connect with the flop (e.g. 8 to a 5-8-A) or complete potential draws (6 to 5-3-7) are extremely dangerous. The problem with these types of cards is that they likely improve your opponent’s continuation bet calling range in the previous street and overall reduce your folding equity for a betting again. At the end of the day, if you try bluffing one of these cards and get called than you’re stuff for the river. You’ll probably be forced to check/fold.