Wouldn't say the raw mark would be 40/50...the scaling goes up and down each year, depends how people did on the test. Remember they are aiming for a nice curve in the results (where the majority get average marks, and the number of people gradually decreasing as you go up and down the graph into the upper and lower quartiles). What I was told is that scaling helps them achieve that curve and also helps with having a clean cut off for each band.
Do not worry much about your raw marks. First the SC does not mean much (as has been pointed out many a time.) and second, if you want to compare marks, a mark of 85 is obviously lower than a mark of 90 despite the fact it's scaled.