Here are a boat speed and prop slip calculator if anyone is interested:
Theoretical Hull Speed = ( Prop Pitch X RPM ) / ( LU Gear Ratio X Constant of 1056 )
Prop Slip = ( Theo. Speed - Actual Speed ) / ( Theo. Speed )
I have found the speed one pretty accurate with small open v-hull skiffs. But where a lot of your guys' boats have extensive flooring, decking, and compartments ... I'd expect lower actual speeds due to the actual weight carried. Also note a jon boat will have more wetted surface on the running hull and will be slower.
Theoretical Hull Speed = ( Prop Pitch X RPM ) / ( LU Gear Ratio X Constant of 1056 )
Prop Slip = ( Theo. Speed - Actual Speed ) / ( Theo. Speed )
I have found the speed one pretty accurate with small open v-hull skiffs. But where a lot of your guys' boats have extensive flooring, decking, and compartments ... I'd expect lower actual speeds due to the actual weight carried. Also note a jon boat will have more wetted surface on the running hull and will be slower.