Hi:
You pose an interesting question, the answer to which I don't think will accomplish your true goal. Let me put forth that the 10% EMC (Equilibrium Moiture Content) you seek is not the relavent goal. Let me slightly modify your question to read, "how do I reach an EMC in my finished piece so as to minimize any movement over time when in the environment in which it will live?" This should be your goal. Not withstanding the academic "peeing contest" in some of the responses here (I too have and am well versed in both Hoadley's "Understanding Wood" and the U.S. Forest Products Laboratory's "Wood Handbook" and have a firm grasp of the physics of drying wood), so let's take the pragmatic approch to your question, as modified.
Knowing the absolute EMC in not important here and of no value. Additionally, the use of a pin type moisture meter will prove detrimental since the holes made by the pins from repeated readings may leave damageing effects on the finished piece. Also, a non-pin type moisture meter will not give accurate readings on blocks or turned pieces of wood. These are designed for use on flat surfaces, ideally milled lumber. The best method to determine when you have reached your goal EMC is by the weighing method. The easiest way I know of to impliment this is as follows:
1) Rough turn the piece you are making from whatever wood you wish, no matter how green or dry it is.
2) Weigh the roughed out piece on a balace that has a resolution of 1 gram or less. Record both the date and weight. If you already don't have one yet, you should be able to pick up balance type scale at a yard sale, flee market, ebay, or new. A well worth investment for all sorts of tasks around the shop.
3) Set the piece in a safe place to dry. Ideally where or near the finished piece will be used or displayed. Reweigh and record the results weekly. Any movement in the piece will occur at this stage of the process.
4) If the piece was "wet" it will lose wieght over time. If it was overdried, it will gain weight. When you acheive no change in weight for three consecutive weeks, the piece is at EMC.
5) Once at EMC, finish turn your project and apply any finishes you wish to complete it. Then, sit back and enjoy a stable piece.
This method does not give you an absolute EMC value, it simply insures that you end up with a non-moving, stable piece. That's you goal!
Peter Toch