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Slip Riging a BulletBobber is often the best way to fish.
Here is a diagram for using a slip rigged bulletbobber.
You set the minimum depth with split shot and the max depth with a bobber stop.
To drop you just relieve tension on the line.
You can control the depth and the location and without recasting.
They even make a little popping noise when you flip direction if you like popping corks.
The only problem is the fish may hit the bobber instead of your lure or bait.