Mixing salt the dbo way

So this has what happened the last 3 times I mixed saltwater

Fill brute trash can to whatever level I decide.
Pour salt in that I think might be right.
Wait 24 hrs and test.
Sg of 1.026
Double check refractometer
Check again and its 1.026
Say, holy $#!+
Do water change lol

I swear I must have some voodoo magic for mixing because I just throw it in there and its perfect.

 

My friend does that and I dont really get it, i always need to add a touch of salt.

 

I get it close, but always have to add a little to get it perfect.

 

After a while you get a feel for how much salt to add, I can get really close when I mix like +/- 0.002!

 

The weird thing is if I mix up 5g its wayyyy off. But if I make a unknown amount of water and dump salt in its perfect lol go figure.

 

how i do it, is fill a 5 gallon home depot bucket, then pour about a 1/4 of the rodi water into the biggest pot i have and boil it, while thats boiling up, i pour my salting into the bucket and start stiring it, once the water from the pot is boiling, i add it to the bucket, every time it come out a perfect 78 degrees and 1.026 SG haha. like magic