I use my airsoft rife. It shoots 15/second. Doesn't kill them but it gets the message across with out a lot of noise. So far, the wood peckers put holes in my neighbors house but leave mine alone. And the squires know better than to get into our bird feeders.
The best part about woodpeckers is they are territorial. So, as long as the current pair are alive they won't bother our house and won't allow other peckers near us.