You need a lot of side spin and enough follow to take the cue ball forward to the first cushion. The nearly-straight-in power shot must be shot with a mix of maybe 1/3 follow and 2/3 side spin.
The shot will not work well on nearly new cloth or cloth that's slippery for some other reason. That's because the side spin will not grab well on the cushions and the cue ball will not "snap" out of the corner.
Most players don't hit the ball far enough from center. How long can you make the cue ball spin in place by shooting a stun shot with maximum side straight into an object ball? 30 seconds shows you have an adequate amount of spin for most power spin shots.
Most players have a very hard time dealing with squirt on shots like this. You just have to get used to aiming way off-angle when you use a lot of side spin and power. The stun-to-spin-in-place shot above will help you with your aiming compensation.
Brian Jones showed me a drill to work on that I guess about 5/6 years ago.
You use just the striped balls, place two inline about 3-5 foot apart depending on how hard the drill is for you. Hit the horizontal plane on the "CB" and use at least a good couple tips of side left or side right.
If you do it right the "CB" will hit the OB and pocket it, and the "CB" will stay in place (horizontal plane w/speed is just a stop shot) and SPIN its butt off either left or right depending on the side you put on it.
Now quickly b/f the spin fades put another stripe in place for your "CB" and stroke the shot with the OPPOSITE Side english you just shot the first shot with.
Perfect would be 7/7 with the 9-15 balls. If the "CB" that became the OB stops spinning b/f you shoot at it then you have to start over. If you miss thats ok too, just as long as the "CB" kills and stays in its place for the next shot and maintains its spin.
VERY TOUGH & DEMANDING DRILL.....
its not for beginners, and intermediate level players will def have a super tough time with it......advanced level players only basically.
If your a beginner or intermediate player and you don't feel like torturing yourself then just shoot the shot 1 at a time. Just set it up, and try and pocket the ball and see how well you can keep the "CB" spinning in place after contact.
Like Bob said 30sec would be basically a maximum to retain spin......If you can do this and keep it spinning for more than 12-15 sec your doing well with it. But to do the actual drill your going to need to consistently maintain a 20 sec or more average spin time as it takes you about 10sec to get the ball in place for the next shot and then another 10sec to shoot.
Like I said this is a VERY TOUGH DRILL, don't let it get the best of you....b/c it will if you let it aggravate you.
Stay focused and take it one step at a time, and no matter how bad you do find at least one good thing that you did well/correctly. Don't ever finish a practice session all beat up, even if you are look on the bright side and find at least one positive note in regards to the session. Its practice, you will make mistakes, but better to make them there than in a live match or tournament.
best wishes,
-Grey Ghost-
Wonder how that happened?