The instruction book for most
chainsaws
will tell you to never use the tip of the bar to cut with because of
the increased chance the thing will kick back on you and cause an
injury.
I broke that safety rule so I
could make a pop hole in our new chicken coop.
It does kick back a little,
but seems like a manageable risk if you brace yourself and don’t get
too close. Framing up the sides first will keep things neat and give
you a cutting guide.