When purchasing a dry core, always use a A taper drill bit and drill drift key, so that your core barrel doesn’t wander away from the true centre and potentially damage the surface area where you’re drilling. Once you’ve started the hole, use the drill drift key to knock the A taper drill bit out of the shank and continue drilling.
What is a drill drift key?
A drill drift key is a tapered piece of steel that’s used to knock the a-taper drill bit out of the drill shank. The a-taper drill often gets stuck in the shank, so the drill drift key is an essential tool to have.