My shotting pattern in the last month has actually changed totally to what I used to do. I know these floats that I'm using today take eight no. 12 shot, and what I used to do is just string them out over a four inch gap in a very basic 'shirt button style', but I've actually changed totally what I'm doing now.
You still want 50% of the shot right near the hook, so spaced out three inches apart, but what I've actually done now is spaced the top four shot so that 50% of my shot over the area of the rest of the rig with the last shot right underneath the float. Now this just makes the whole rig really stable and what I found when you just had all your shot just spaced out at the bottom, is when you laid your rig in there was a delay from where the shot was sinking and the float was catching up.
Putting your shot on like this, with 50% of your shot near the float and 50% below the whole time the rig is settling I really feel like I'm in contact with the rig and everything is really finesse and you can see every last little bite.