What weight do you use for about 16 ft water for 3-4 inch bait? also do you fish directly beside the boat or do you guys cast it out thanks

use a 3/8 oz. weight , good for 15-25 ft. as far as dropshotting , i like to cast it out up to 20 feet away from the boat , 16 ft. of water is a little close for d.s. directly below in my opinion .....

I've used 1/4 oz. down to 45' with no problems. Sometimes I fish directly beneath the boat; other times a short cast away. Depends on the structure I'm targeting and the depth. Here's a recent link:

http://www.bassresource.com/bass_fishing_forums/YaBB.pl?num=1266369035

I use 1/4 ounce as well unless there is a lot current. Whether or not I fish directly below the boat is based on water clarity. Unless the water is very clear you should have no problem.