Quoted:
If you compare the 'Dimples' from the Shot compacting against each other when taken from a Water Box, you will find almost no visible difference between the two.
I'm not sure exactly what you are saying, but as a matter of fact, I have shot a lot of buckshot into water jugs.
Here's some #3 buck on the left compared to some 00 Buck on the right.
You can plainly see the deformation of the pellets, caused by their smashing together as they go down the barrel.
And here is some "before and after" examples of soft lead buckshot fired from a Taurus Judge into water.
They flattened out very badly, certainly more than "dimples".
Look again at 556A2's avatar up the page. That is what plated/hardened buckshot looks like as it leaves the barrel.
There is a reason that they plate the buckshot.