Not to brag but I think I'm one of the better bunker players for my skill level. It's Definitely the strongest point of my game. I think partly because I belong to a club designed in the 20's by willie Watson and George Thomas so it has similar bunker style to Riviera. cc Very deep bunkers surrounding small greens. So pretty much every time you miss a green you get some bunker practice.
I play 90% of my sand shots with a 60 degree wedge that gives me comfortably about a range out to 20-25 ft. If I have to hit a longer shot than that then I'll go to a sW or 52 depending on the distance and height of the lip.
But my biggest key and it's very simple is the staple of the three best bunker players of all time all your weight on the left side at impact and I mean all of it. Trevino , Player And Seve all do this ( by the way one of my sons name is severiano). Seve although sometimes starts with weight centered and as he takes the club back he transfers his weight to his left foot on the backswing. That's what gives him that interesting look. I worked a lot on the Seve short game techniques with Mac O'grady and it gave me the ability to hit really high soft shots.
Trevino and Player and Seve in the bunkers actually just start with all there weight on there left side and they keep it there. Trevino credits player for his bunker technique. I believe this technique is the easiest and is what I now employ.
This technique although it seems simple gives you too really great benefits.
1. Steeper angle of attack. Trackman has enabled us clearly to see the measured spin on a shot and has made my understanding of increasing that spin via there spin loft measurement clearer.
To get more spin on any shot we need to either one increase angle of attack while maintaing the same loft of increase loft while keeping the same of angle of attack. Or diverge both at the same time increasing angle of attack while also increasing loft.
On a normal full shot this is tough because when you hit more down on a ball, say placing it farther back in your stance you also decrease the loft the same amount so there is no increased divergence between the AOfA and the loft you'l get the same spin the ball will just fly lower. And vice versa with the ball farther up in the stance. Your AOfA will be shallower but your adding loft so the spin will be relatively the same the shot will just go higher.
In a bunker though and a lot of short game shots you have the opportunity easily to increase angle of attack by playing the ball more back of low point and increasing the loft by opening the face wide open.
Trevino Seve And player, play the ball further back than most and get all there weight on there left side throughout the shot this gives them a really steep angle of attack. Then they just open the face accordingly and wahla a high spinny sand shot. The weight left the whole time actually gives you greater accuracy as well as it's easier to hit the sand in the exact same spot when your cog doesn't move.
Kinda long winded post but summary is all your weight on left side ball back like middle of stance and open blade up a lot. Then go thump that sand and get a feel for your aim and distance with your length of swing.
Here's a great Seve video at the end there is some slo no bunker shots http://youtu.be/uIXjPMYjLPk