Gday and thankyou for taking time in your very informative reply good o mate :O)It varies lots depending on type of timber and moisture levels.
Vinces dry redgum came in at 2.4cu mtr per ton. Typically your looking around 2 to 2.5 Cu mtrs per ton for Australian hardwoods when under 20% moisture content which is where you need to be for firewood.
12% moisture content is the best you can get air drying it. It dries out at about the same rate whether you keep it under cover or outside....tests have shown that if it is left outdoors to dry it can dry marginally faster as the rain is thought to help keep the capillaries open to assist with drying but the difference is only marginal......same with splitting, only a marginal difference.
If keeping the timber for firewood I cut it to lengths of 300 to 450mm long. ...my rule of thumb is to allow 1 day for every mm of log length divided by 2...so a 300mm log will need 150 days drying time to get below 20%
My trailer holds just over 5cu mtrs. When full with dry stuff tightly stacked it's just under or just over 3 ton gross and the trailer weighs 660kg. When wet well over 4 ton gross
cheers The Red fella