To answer your question, the wood to use is split hickory. Split, rather than cut, or sawn, because splitting the wood followes the growth rings, or " Grain", while sawning the wood often cuts across grain, giving you " run-out". Run-out is a weak spot, and will be where the rod breaks if and when it does.
Talk to Log Cabin, Dixie, Track of the wolf, and any other supplier that may be close to you. If possible you want to pick out your own sticks. You can by the end ferrules, and jags to make the fitting for the rod(s), but you always want to remember to pin the ferrules to the rod, by drilling a cross-hole through the ferrule and rod, say for a common nail, at least 1/16" inch, and then run a pin through it, peen the ends down, and file them flush. I also use epoxy resin to help hold the pins in place, and use the same epoxy to glue the ferrule to the end of the rod. If you put a handle, ( Door knob, T-handle, bone, antler, etc.) on the other end of the ramrod, to make a " Range Rod ", used for loading, cleaning and the occasional ball pulling-- pin the handle to the rod the same way you pin the ferrule to the stick. You can taper a hickory rod to fit easier into the stock of your gun, and still have a strong rod.
In order to not be breaking rods, DON'T push them done the barrel from the opposite end. Reaching that far out makes you use your large muscle groups, and you can put too much pressure on the stick, and maybe bend it so that it is breaking before you can stop putting pressure on this. Instead, always run a rod down the barrel in short, hand-over-hand strokes of no more than 8 inches at a time. Yes, your finger have to wrap around the rod, and they may get dirty, but they look a lot better even dirty, without a ramrod run through them. Turn your hands palms away from your body, thumbs down, and grab the ramrod with only your fingers-- NO THUMBS. if for some reason a powder charge ignites in the barrel, the body's defensive reaction to pain to the inside of fingers, is to open those fingers quickly as if you were dropping a hot potatoe. That action will save you your fingers, and skin. Of course, when you are pulling the rod out of the barrel, you can take it out with one long pull on the handle, or back end. Just be careful about bending the rod at the muzzle. If you have to choke up on the rod with another hand, do so. Save the rod.
One of the rarest things in nature is a straight stick. Plants tend to arc towards the sun at its strongest position. Finding a straight stick, even one that is split from a tall hickory tree, represents a real " find ". The straightest hickory trees grow up from the bottom of steep ravines, where they are protected from the wind, turning them until they are perhaps 30 or 40 feet tall, and straight. You can get a lot of ramrods out of a hickory tree like that. I have seen hickory trees that are no more than 12 inches at their base, and 8 inches 6 feet off the ground that top out at 60 feet and taller, and have the first 35 -40 feet as straight as an arrow, all because they are protected from winds in the bottom of ravines.
The wood dowels sold in hardware stores are usually pine, or birch. They DO NOT make good ramrods, and you will almost always find run-out of the grain somewhere along their length. And, when you sight down them, you rarely find a rod that is truly straight its full length.
