[dertsap]

you could go with a solid carbide drill ,if it is properly on center the hole will be dead nuts
seco has or had an insert drill that has one solid insert at the tip ,this thing had multiple tips for drilling cboring and milling . i experimented with one on 4140 with .75"dp holes ,with it being a loaner tool from our supplier we ran it until it blew up to see how many holes max we could get out of one insert , we got a little over 1800 if i recall correctly , the insert was roughly 100 bucks , the speed we gained out of it paid for the insert , the holes were perfect size and with a good finish

i don't think the machine we ran it on had thru spindle coolant