A wise old armourer from WWII told me "The first round goes through them, the second through the roof." when asked what happened "I gave them a warning shot and they kept coming and I was afraid for my life."
Here in Aus and other countries I guess do not have the luxury of a home defense weapon only stuff you can squirell around the house to either club'em or stab'em but its no problem for them as they are criminals and probably in possesion of a stolen cut down shotty/rifle or H/Gun.
For us here they are not going to wait until you unlock your safes (Bolts seperate) to put your rifle together then unlock another safe for the ammo load it then join the party, if we did plug them then we would be facing some stiff jail time plus the family of the either injured or dead perps suing your A*se off through common law.......
You have my sympathies, mate, but indecision can be worse...