You need to bore a bunch of holes through some timbers, but your drill just isn’t up to the task. If you have your impact driver handy you can do the job with one of Irwin’s impact-wrench utility-pole auger bits.
Irwin designs these bits with a medium-fast screw point to bore through creosoted poles and construction timbers without clogging, binding, or stopping to clear chips. They heat-treat the full length of the bits so they resist bending under heavy use.
These auger bits come with hex shanks compatible with either 5/16″ or 7/16″ drive impact drivers. Sold in diameters ranging from 9/16″ to 1-1/16″ and in lengths of 18″ and 24″, they run $30 to $55 per bit.