We are running a bunch of hard maple solids. We are flipping parts after first side and doing a drill/countersink on the second side. Seems most combination bits are adjustable but the depth is too deep at the shallowest set screw depth on the countersink portion of a bit like this" https://www.toolstoday.com/v-9965-55608.html

I dont want to do this in two operations (tool change). The setups we have been using the set-screw countersink tends to slip over time. (surely the countersink is getting hot and the set screw loses its grip).

Anyone know of another option that will allow a single operation? We are just poking a clearance hole for the screw and the countersink for a screw and hardwood plug on the second side (.8125 thick). The .8125 seems to be the issue in that if I retract the bit that far up in the countersink and grab on the outer diameter of the pre-drill, it just slips. Even the high end pre-drills have flats milled on the flutes for the countersink but they still dont hold.