Because geometry tolerates no argument, sometimes the bottom-dead-center of a pipe's tobacco chamber and the bullseye-dead-center of its mortise floor cannot be connected with a straight line.
It isn't a brand-dependent thing, or even (necessarily) a "quality thing". It's simply three dimensional reality.
It was the case with this early production "Ashton 120". Nice looker, wonderful smoker.
The airway entered the mortise "high", however, which made running a pipecleaner through the pipe without taking it apart impossible.
Easy-peasy solution:
The yellow line is the border of a ramp that was cut into the bottom of the mortise with the tool shown. A standard-issue conical Dremel burr cutter that had its sharp outer edge ground smooth on a belt sander while spinning.
NOT removing the side edge pretty much guarantees you'll have an ugly time of it, gouging the mortise walls while trying to control the cutter (which will keep grabbing the walls in a feedback loop of briar mayhem).
NO side edge will make it stupid easy. No grabbing, just insert, push downward a bit, blip the throttle, check the cut, repeat as needed until the ramp is what that particular pipe's geometry calls for.
I've done it to hundreds of pipes for many years and never had a problem of any kind.
Should the factories do this? Of course. Do they? No. Why? Who knows... (Most of the better artisan makers DO cut a cleaner ramp when necessary, though)
Anyway, it only---
literally---takes two or three minutes, and is something anyone can do who has normal coordination & eyesight.
The world's flowerpot manufacturers and landfill operators might hate you, but the PipeGods will smile.
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