in doing so they usually go with 16 slot or 100 slot - there are other variations just that those 2 are the most common.

with a 16 slot, the last character determines the winner - 0,1,2,3,4,5,6,7,8,9,a,b,c,d,e or f

with a 100 slot, the last 2 digits in the hash determine the winner 00 thru 99

that being said, there are many variations at which to do it.

with 30 slots what in the hash will determine the winner? the last 2 numbers? and if the numbers are not 01 thru 30, just roll to the next block until there is a winner?

I also apologize if I have derailed your raffle - was not the intent.