I have a bit I use on pilings and dock work.
It is about a 5/8 wood bit welded onto a long shaft....
Works wonderful.
I use a power driver, and pull it out continuously.......
It is a ship auger bit......and helps move the debris up and out...
The shaft is smaller than the actual bit so that debris has room.
john

"SteveB" wrote in message ...

I want to drill long ways through a 4 x 12, then as far as I can into
another. I want to then insert a piece of rebar in the hole. I
estimate the hole will be 24" deep. Are there 5/8" bits this long?

Steve