Bents are often deliberately bored with chambers that end slightly below the draft hole. It's to reduce the amount of goop smokers suck into their mouths while smoking.
Generally speaking, and this will be a surprise for some of our members, most pipe carvers actually know what they're doing. I know. Shocking. I realize that it's somehow fashionable for end users to act like they're more expert than the person who makes the equipment, but in truth that's bullshit.
Smoking a pipe isn't rocket science. Take pipe, insert material to be burned, set fire to it, draw air through airway to keep fire burning, burn down material, empty chamber when done, repeat.
On the other hand, smoking a pipe to get the best out of it requires experience, learning how to balance the components, the pipe, the material, and the burning process, to get the most enjoyable result.
People smoke pipes for different reasons. Some want to look interesting or hip, some like creating billowing clouds of smoke. Some look at it as simply a delivery system for getting a nicotine hit while others are more focused on flavors and not so much on the nic hit. So what do you want to get out of pipe smoking?
I'm into pipe smoking primarily for flavors, so I've learned how to maximize that result. Generally it involves slow smoking, low moisture of the tobacco, and a lightly firm pack. I want the tobacco to simmer at the edge of going out because that's when I get the most intense flavors. I just keep it simmering around the glowing cherry, because that little bit of steamy smoke carries the flavors. I don't smoke hot. I smoke slow and cool.
As for how far down do I smoke a bowl? It varies. Sometime I'm surprised when I'm suddenly sipping ash. Other times I'm done when a bowl's half done. I might finish that bowl later, or the next day. I might just toss it.
Different tobacco blends burn differently, so don't develop any blanket sort of expectation. There are times when I can put a lit bowl in a coat pocket while I go into a store to pick up some items, pay for them, then exit and pull the pipe from my pocket and keep smoking without a relight even though it's been 15 minutes or more.
That's because that blend will continue to simmer, not because I'm so masterful. Well, I'm somewhat masterful, but not that masterful. Other blends need more constant attention, and some of them burn like they're coated with fire retardant.
Thing is, practice makes perfect. You get a sense of how it clicks together for you by doing it. You can get suggestions but you won't understand them without experience and practice.
Want to really know how to smoke a pipe? Just smoke the goddamn thing. Experiment with moisture levels, packing densities, etc, etc, but smoke the goddamn thing and don't worry about it. When it comes to pipe smoking, experience is the only teacher worth a shit.
