Trey Combs book on Steelheading has some of his formulas for sink tips and shooting heads. I can say that a sink tip on a fly rod feels like s#%&. Having said that, I have a 30' type VI shooting head on my 8wt that sinks like a rock, but will throw a hell of a lot of line. Experiment and practice!
You don't always have to single or double haul a sink tip, I find that I roll cast mine 70% of the time due to lack of room.
Good luck!
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Flyfishing, the gentler art of ripping lips.