Here is the process I use to rough out an osage selfbow. It is quick and accurate and saves time for real bowmaking. I rely heavily on my 12", 1/2 HP Craftsman bandsaw for these this task.
Of course we start with a stave. Here is a beauty. Indiana osage cut in February of 2002. She's got straight grain and about 2.5" of natural reflex. I got this one and several others from 3 trees all growing together. I like to take off a lot of the excess wood and square up the belly side and the sides first. This helps in later steps.
Here I'm taking off the belly ridge. I try to keep this cut parallel to the back, or bark side adjustiong for any twist in the stave. This will help later when we cut the bow out to keep from getting thin or too angled sides. We want everything we do here to lay the foundation for a trued up layout later.
OK here I do the sides. The same concept applies. True everything up from the start and we will have a much easier time later. The last two pictures are my goal. Now we have to chase the ring. Here's a quick way for that.
I use the bandsaw to take the sapwood and even some of the heartwood off. I look the end of the stave over very carefully and choose a ring I want. Every stave is different and on some really bumpy staves, this is tricky. I have never screwed one up. You just have to take your time and think about what you are doing. This is one reason a squared up side is so critical. You just cant run a non-planar material across the bandsaw table and expect an accurate cut. You can see I am not taking all the sapwood off in the left picture. This is to allow for the crown. This stave has a fairly high crown as you can see in the pic below. On some staves you can go right up to the heartwood. Others, you have to angle the stave through the bandsaw at times to accomodate twist and knots and such. It's not for the faint of heart or the inexperienced. I have cut out 100 or more bows so keep that in mind.
Here's a view at the end of the stave. The second or third ring into the heartwood looks good to me.
The end result. You see where the sapwood remains on the sides and the crown is chopped in a few places. That's fine. On the secod picture you can see I got 3 rings into the heart at the deepest place.