There are a lot of factors that come into play when throwing bait in the surf. Funny, this part of casting and surf fishing has never come up. Usually, the question is how to cast or how to cast farther
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When you cast, you want to cast and put the bait where you want it. You don't want to rely on current or waves to take it, unless you are working a rip or trough(which I will come back to). If you rely on the current and waves, either your bait will be back on the beach or tangled up in your now, unhappy neighbor
. So for your normal surf casting, most people cast it out as far as you can. Like Jason said, you want to get past the breakers, at least. However, you don't be out really far to still catch fish. Many fish, for me, most of my fish are caught 5-10 feet off the tide line. Getting past the breakers will give your sinker the ability to hold better. Almost all of the time, you want to put on enough weight to keep your bait still or hold. You should always attend your rods, otherwise you may be chasing them into the water. You can also leave your bail open, leave the drag very loose or use a reel designed for that function: a baitrunner or baitcasting reel. If you leave your bail open, you can very easily get wind knots and have your line all over the beach. If you leave your drag loose, you may lose some fish. So whatever works for you or is the easiest.
Now, if you want to drag bait or work bait out a rip, in a trough or along a jetty, you won't want to put on as much weight...just enough to hold bottom. In these cases, you will let the current and water do the casting work for you. If you see a really nice rip, you just need to get your bait into the pull and off it will go. Fish will hold at the end of the rip where it comes through the sandbar. This is great structure for surf fisherman and alleviates having to power cast out. Troughs will run horizontally to the beach, so you will want distance on either side of you and you will want to cast into the trough and let it ride. Fish swim through here and predators could be swimming or waiting at the end of the troughs for a meal. You can also cast your bait out and just work it into the beach on a wave aided drift or along a jetty. You just need to find the way the current is running and use that to your advantage.
So you have lots of options, deadsticking and relaxing, throwing bait to hold and just watching for the bite, dragging bait and working the bait almost like a lure in the right conditions and structure. There is a time and place for all of these, although, experimenting and variety will work best.
Good luck, enjoy and be safe!