When last smoked this pipe I had to relight 10 times at least to get through a bowl - after this mod, I smoked a bowl today with just 1 relight!
This is by no means my idea. The concept is from this article: http://pipedia.org/index.php?title=Airflow:_The_Key_to_Smoking_Pleasure
The draft hole should be bored out to a minimum of 5/32" all the way. The hole in this pipe was only 1/8" diameter in the bowl and a puny 3/32" in the stem. It whistled while smoking - not anymore!
Note: A disclaimer to those opposed to smoking. I too am opposed to smoking - but I reserve my opposition to cigarettes. A disgusting habit, and guaranteed deadly. Nevermind the awful smell!
So please do not rant here about how much you dislike smoking. Pipe smoking has been proven to carry a very low risk compared to cigarette smoking. Some studies have found pipe smokers to live longer than non-smokers.
Note 2: A pipe smoker should never inhale! Doing so is a serious health risk!
Step 1: Tools
Note how there is no drill motor here. That's because you're doing this by hand. This is fine work and doesn't require much power.
In all I probably took 45 minutes to do this mod, but it was the first time and I was being very cautious.
Step 2: Drilling Out the Bowl
Just twist the bit in gently by hand. There's no need to use big muscles here.
Be careful that the bit follows the draft hole exactly or you could mess up your bowl pretty bad!
Step 3: Drilling Out the Stem
Remove the bit regularly and clear the swarf, which somehow comes out in copious quantities.
I would recommend working from both ends instead of fighting all the way through. Before each new bit, make sure there is enough clearance that the bit won't go through the side.
I was very careful and still almost cracked the stem as in the second pic. Fortunately that is just a bulge with external splitting, not a crack - it is still airtight. Whew!
Wash the stem out well afterwards with running water. It will be full of vulcanite dust, which you probably don't want to eat.
Step 4: Enjoy a Better Smoke
You probably shouldn't try this on a prize pipe due to the risk of damage (at least not before some practice). But if you have a crummy pipe that smokes poorly, why not try it?
Note: this crummy pipe is also my only pipe. However, the risk was worth it to me, since the thing didn't smoke worth a damn!