I think 40 yards on whitetail is a long shot (perhaps too long). A lot can go wrong with (Minnesota) whitetails.
For some reason western (Idaho) deer seem more curious and less flighty.Therefore they do not seem to "jump the string as much" Plus the foliage is hardly as dense. Elk seem dull and have a hard time jumping the string. I think out west your maximum range depends on your ability to group your weapon....out to perhaps 70 yards(not me, I like 50). But Minnesota whitetails are too skittish to attempt such long shots.IMO
