I managed to get my FAC with .17HM2 on it just after my fifteenth birthday. The best way I found was to get a 'mentor' - someone who already has an FAC and is willing to show you the ropes, so that when you apply, you can say you have some understanding about the rifle and are safety conscious.
A mentor can be anyone who owns an FAC, (mine was a mate of my dad). But if there is anyone on any shooting forums (including this one) near your area who are willing to let you use their rifle(s) then that is the best way to get an FAC.
It also helps alot if you join a club, this also shows you