Best way to make a deep slot Drill Chain?

Best way to make a deep slot Drill Chain? slot drilling Need to give my 100% every single day: Washington eyes spin all-rounder's slot in Team India drill a 6-km deep hole in Koyna, Maharashtra slot props 6PC slot drill set 3-12mm, 2 flute

slot props end mills don't plunge, the cutting edge doesn't meet in the middle so there is an area that doesn't cut a slot drill has cutting faces that

slot mega 777 Milling the keyway, then drilling and tapping the cinch bolt My only concern is if the bore will change after I slot it? I AASONS Four Slot Wood Auger Drill Bit, 14 Hex Shank Twist Drill Bit, Wood Drilling Bit, 4 Slotted Quick Change Auger Wood Drill Bit For