I read somewhere that black walnut was stronger per pound than english walnut. That actually makes sense to me since I'm sure balsa wood is stronger per pound than either black or english. But, lets face it, gunstocks are made to a size that is pretty much dictated by the previous stock or ergonomics and not usually sized by the guy making a replacement stock.
My own collection of blanks and few stocks that I've made suggests to me that, in general, english walnut is of higher specific weight and possibly stronger for a given cross section than black or claro.
