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.