We have unloading bays outside all Guardrooms, think brick built box 2m wide (2 guys per time) approx 1m deep and 1m front-rear filled with sand
sometimes 2 tubes set into it.
affectionately known as the 1m range,
possible overkill for your residence, but you get the idea.
However, I dont know about your side of the pond but here,
UNLOAD means to remove the magazine/belt
operate the working parts to the rear.
check inside chamber, face of bolt and mag well to ensure no live round is present
working parts forward, fire off action if required.
if it makes a loud bang, you are in BIG trouble (I would lose my rank and face a big fine)