Wisdom is relative.
is it wise to drill out a lead bullet
You could probably do it successfully. Now, as to the wisdom of doing it, welllll.....
How many "old lead bullets" are we talking about, here? Are they uniform to begin with, or is it an assortment? Are they corroded, or have they been well stored? Are you willing to do the fiddling around to "get it right" and go to the expense and effort of making or buying the necessary equipment?
With less than several hundred bullets that are uniform and of high quality, I can't imagine it'd be worth your while.
Tell you what I'd do. I'd take the "old lead bullets" to my friendly local recycler, sell 'em for scrap lead, go down the street to my friendly local gun shop, buy some brand-new hollow points, go home & load same, and go out shooting. But that's just me.
Another thought: If the bullets appear to be REALLY old, I'd check with a collector first as to their value before selling them for scrap.