This article is from the Bagpipe FAQ, by Denise McNickle firstname.lastname@example.org with numerous contributions by others.
Well, no. The practice chanter approximates the sound you get from the
pipe chanter, but not entirely. If you finger the notes incorrectly on the
pipe chanter, you'll find that you often fail to produce a true tone. Also,
you'll find it impossible to correctly perform many of the common gracings.