I like to pack mine light to start. I do a char light and then tamp. Do another light and that will be my puffing light. It will last for about 20-30 min. I will do another tamp and dump the loose ash and relight, this one gets me about 15-20 min and by that time it is pretty much out.
With all that said, I like a smaller bowl and I like my tobacco on the dry side.
The dryer the tobacco the easier it will be to light and the dryer the smoke will be.
Also, if you are smoking an aromatic, that may have something to do with it too, they a lot of propylene glycol and that can make it hard for the pipe to stay lit.
Pipes are not like Ronco ovens, you can't just set it and forget it, they are like a woman, they need attention and fussed over to be enjoyable.