Quote Originally Posted by nitrowarrior
Tech? you wanna handle this? Bottoming tap has threads all the way down the shank(or fluting) as it goes in, it does not leave material untouched and will "bottom" out in the end blank (bottom) of the hole . Use a BFH, but make sure it a lead shot mallet, no steel hammers. I can can't see the problem first hand. Follow Tech's instructions. I own the kit to solve this. It is not readily available to the public so I am gonna tell you to go old school as much as I can with you.
Thanks warrior, I didn't see your answer when I posted.