Victoria has minimum cartridges for Deer. They have in the last couple of years stuffed up a fairly good system. Yes there are those who are skilled enough to shoot and kill deer with minor calibres. Most are not and the idea is to prevent as much as possible the wounding of deer that could then die a slow death. Also the larger calibre allows for shots from non ideal angles. Yes there are those who will not pass up a shot when they should and it provides more penetration if a follow up shot is required.