A combination of the crossbow with the upgrade that grants mana on a headshot, and the frost bracelet (seriously a very powerful tool, I never slay orcs without it) will allow you to stunlock multiple ogres indefinitely, while also holding them perfectly still allowing for easy headshots (as opposed the the crossbow's secondary fire where they sway their heads).
In combination with a fully upgraded crossbow, you can hold an ogre perfectly still and take it down in 3-5 headshots, normally before the frozen state is even broken, and if it does break, you can just freeze them again.
This works even better if you use the secondary fire and have upgraded the bracelet to make enemies frozen by your secondary fire take more damage. Not only will it freeze many many orcs and ogres, but it lasts much longer (I think it's over 5 seconds) and they will take more damage as well.
The only problem with this strategy is frost ogres, who are immune to the bracelet. In this case, you're just going to have to stunlock it with your crossbow's secondary fire, and aim at the moving head.
There is no other weapon that kills as quickly as multiple headshots from the crossbow.