Since becoming master, I realised I hadn't mastered all of my game so I've been mostly playing practice rounds and taking notes of all my short play shots (on various courses), collating that information and coming up with a formula, of sorts. I also noticed there wasn't much advice on getting from the sand to the pin so hopefully this helps you as it has me.
Firstly, I'm mostly using a L39 Z satin TP64 with an average distance of 50yds and I practice with starter balls although when I use the L11 Srixon Z-star balls I get the same results.
(28) 24yds, 4ft up from 20% (+4)= 32 dropped 19(59%), ran 4…….-1
(30) 24yds, 6ft up from 20%(+5) = 35 dropped 21(60%) ran 4……..+1
These are just 2 of scores of examples I have where the 1st bracketed number is the combined length(yds) and elevation (feet are added as yards, not converted into yards). 20% is the maximum sand lie and the second bracketed numbers is the yardage I added to my swing to compensate for that lie. 'Dropped' is where the ball met the green. In both examples, the ball ran 4yds and in the first example, the ball stopped 1yd short of the pin and 1yd over in the second example.
I've omitted explaining that the ball dropped 59% and 60% of the total hit because I got so many differing results that I couldn't see any correlation with these.
Therefore: From 20% sand I found that combined yardage (of distance and elevation) of over 35yds where elevation exceeds 6ft needs 3 yards added. (ball will roll further)
Over 35yds (combined) with elevation lower than 6ft, add 4yds
Less than 35yds (combined) and elevation is above 5ft, add 4yds
Less than 35yds and elevation is below 5ft add 4/5yds.
So, to clarify. If the pin is 25yds away and 4ft above your lie, 25+4+5 = 34yd swing.
Of course, uphill, downhill and greens that break hard left or right will need to be adjusted to. I've also not mentioned wind either. Unless your playing in high winds, these figures are good in my experience.
From 40% sand.
34yds, 9ft up from 40% = 53
dropped 27(51%), ran 7……0
24yds, 4ft up from 40%(10) =38
dropped 19(50%) ran downhill 9…+4
In the 1st example I added 10yds and nailed it. In the 2nd example I added 10yds but didn't compensate for the downhill slope on the green. Although I holed it in the first example, it was traveling a fair bit so i recommend adding 9 instead of 10. To hit 53, I used a cleveland 60w with average distance of 80yds.
Therefore:From 40% sand combined yardage of 20-30, add 12
combined yardage of 30-40, add 11. 40-45, add 10 and over 45, add 9.
Again, compensate for your surroundings.
I'll forego further examples and go straight onto 60% sand lie
Combined yardage of below 30, add 16yds. 30-40, add 17. 40-50, add 18 and over 50 combined yds, add 19.
I tend to use full back spin on longer shots, where greens slope away from me and on deep lies. All others, I place the dot where the sand meets the ball.
I apologise I haven't added in other sand lies but I just didn't see enough of them to get a reading.
Also, some bunker shots that are shorter than the figures I've given or where the elevation is a large %age of the combined total will need either pitched or flopped as you will either drop it short or hit the fringe which tends to slope down into the green on many courses and catapult your ball well past it's intended target.
Getting from a fairway bunker is a different beast altogether so my advice would just be to aim to get back on the fairway and take it from there.
Remember, this isn't an exact science as all courses differ and you may use different clubs and balls as I do but If you use this as a baseline and tweak it, you'll find you'll get within 3ft of the pin every time.
Finally. check out three of my bunker shots I've saved from the same round at Kiawah on 12/16/11 to give you an idea what practice and note taking does for your game.