Rakesh, there is a good article on tigers in India in the June issue of Outdoor Photographer. The guide says that the chances of seeing tigers in Bandipur is relatively low, here are his relative ratings:
Here is the link to the full article, its worth a read:
I have been to India several times on business and always bring some camera gear but never long lenses; it would be great to do so to shoot wildlife sometime. I will be in Bangalore later this fall, any photo opp suggestions would be appreciated.