For Surf fishing off a beach, with OTG (Off the Ground) or Pendulum style casts, a long drop gives better distance and control - also helps to load your rod ... I would say at least
3/4 the length of your rod is the drop to use.
I do not see how it is possible to utilise your rod to the max with a shorter drop

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With a shorter drop you will not really be casting to the full potential of your tackle. To get distance, you must build up the power smoothly and deliberately with the sinker travelling over quite an arc to build up the necessary force and momentum - this can only be accomplished with a long drop (and body movement).
A short drop is OK for an overhead "thump" or "snap" cast, but do not expect much in the way of distance ...
If your'e casting well with a short drop, you'll probably be amazed at yourself when you change to a longer drop

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A longer drop will also allow the rod blank to load properly and to unleash the power of the cast properly and smoothly and may help to curb or cure an "unruly" or "whippy" tip at the end of a cast ...