I've shot a numerous goats and hundreds of sheep with .22lr headshots. Outside 30 meters I dont bother.
Usually use Winchester Powerpoint 40gn.
Best results come from hitting the soft spot between the eye and the ear especially for hard headed animals like Rams, or the back of the head as it will hit the spinal column if it hits a bit low.
That being said I've had it go wrong on enough occaisions to not generally recommend it unless you have to.
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