Below is a post copied from the PBS site by Larry Schwartz on, which succinctly explains the way I have always envisioned the mechanics of static and working tipped bows.
“That design, with the thick recurve tips, is called a static recurve. It is a design that originated in Asia. It is most often associated with Bear Archery's original bowyer, Nels Grumley. Of the four models of bow he made by hand for Bear in the 1930's and 1940s three of them included this feature, although he referred to them as brush nocks a the built up area helped keep sticks and brush from getting stuck between the string and the bow limb. It is called a "static" recurve because it only "re-curves" in one place where a full working recurve limb curves/flexes all along the curve part of the limb.
The static design is less efficient than the full working recurve limb that is used by most everyone these days.
The recurving part of the limb acts like the cam or wheel on a compound bow and moves faster than the flat part of the limb as it returns to its undrawn position. This "flips" the arrow faster at each point along the recurved part of the limb, just like the cam does on a compound. On a working recurve limb you get this affect along the whole length of the curved part at the end of the limb, on a static recurve you only get this effect at one point, right before you get the long built up limb tip.
So, that's your archery history lesson for the day. I hope you found it both interesting and informative. It's always nice to know how and why your equipment does what it does.”