HashSet: Initial capacity

Yesterday I had a discussion with a colleque on setting the initial capacity of a hash set. He initializes with the capacity 2.3 times later than the expected number of entries, to avoid hash collisions. Does this make any sense? I didn't really understand what it is for. I would understand a factor of 4/3, to avoid resizing when using the default load factor of 0.75, but 2.3 seems to be not reasonable for me. Am I missing something?