Pinpunisher: A lot of nights when I'm leaving 7 pins it's usually due to throwing the ball too fast, pushing the ball longer down the breakpoint and then ringing it around high, or sometimes if I try to coming in from a tight angle instead of letting the ball hit a little lighter to carry the corner. As everyone else in the thread stated, we would need to know what type of conditions you bowl on (long oil, short oil, how many feet they oil, heavy concentration of oil where, lighter where, as well as your style, where you like to play on the lane and how fast you throw) to be able to help you a little better.
Matt