I think the iron wood you are talking about is Hop hornbeam. Hornbeam aka muscle wood is a totally different wood. I think another name for it is blue beach. HHB makes great selfbows, hornbeam doesn't.
Red oak as you buy it at your local Lowe's, etc. isn't the same quality as red oak you cut and split yourself. A red oak stave is superior to the red oak boards you can buy at Lowe's.
Some ashes are good selfbow woods but others are not. I'm not sure if black ash it a good one or a bad one as far as selfbows go. I've only used ash a couple of times and don't consider any of it good for selfbows, at least not for me. Historically it was used by Native Americans as bow wood. Ash does make good split wood baskets.