Kukuzans is operational again now: http://www.kukuzans.co.za/ba_hippo-hunting.htm

Quote: "One of the unmistakable animals of Africa, the portly hippo has been the subject of many jokes, tales and legends. The early explorers first called this strange looking mass of blubber the sea-cow and hunted them for a plentiful supply of meat and fat.
A fully grown hippo bull can weigh in at 2 tonnes, move at a speed of up to 20 kilometers per hour and brandish scimitar shaped ivory canines over a meter and a half long! During an average night's feeding, they can eat over 100 kilogrammes of grass wandering over an area of 30 kilometers.

The hippo is responsible for more human deaths each year than the crocodile (believe this, it really is true!). They are extremely territorial and will attack boats and canoes as well as people in their path. However, if their territory is respected they are no more than floating lumps of blubber...

Habits
Hippo spend most of their day submerged in water and sunning themselves on river banks. They occur in groups or pods up to 20, usually led by a matriarch with a herd bull always in attendance. Bulls will constantly have to defend their presence or be ousted by another willing male. Their fights are fierce and often fatal for the loser. Their thick skin does offer some protection however their teeth are razor sharp, easily piercing the 3 inch layer.
Despite their size, hippo are a favorite food of lion and are sent scampering for the safety of water whenever lion are about. It appears lion are able to kill hippo by jumping onto the running animal's back and pulling its muzzle down beneath its feet, tripping it and causing its tremendous weight to break its own neck.

Hunting Tips - the Hunt
To hunt a hippo is probably as challenging as beating a fly to death with a rolled up piece of newspaper. Stories abound of ferocious hippo that charge out of the water for no reason, trying to kill all passers by. While some old bulls do get defensive and a bit cranky, 90% of hippo are shot while they are in the water from about 50 yards away. A bull is chosen and one simply walks up to the bank of the river or pond, takes aim, waits for the hippo to present a good head shot and bang, hunt over.

The hippo will usually float to the surface within half an hour or will be visible in shallow water whereupon it is retrieved and hauled to the bank. This is often the most interesting part as local fishermen or the PH's own trackers wade into the crocodile-infested river to tie the rope around the hippo.

Most hunters will shoot hippo, however, as it makes excellent lion bait and the decision is usually a matter of necessity rather than choice.

Hunting Tips - the Calibre
The most common shot for obvious reasons is the brain shot. Directly between the eyes or between the eye and the ear are the best areas to aim for.

Although the .375 magnum is the minimum legal requirement for shooting hippo, I have seen hunters use 7mm Magnums, 300 Magnums (even 30-06) with good quality solids.

Hunting Tips - Where
The best countries to hunt hippo are Zambia, Zimbabwe, Mozambique and Botswana. South Africa does have hippo on offer but they are expensive when compared with the countries to the north.

The hunting of hippo is usually incidental to the hunting of another species such as lion or buffalo."

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As stated, I know I've read similar accounts elsewhere over the years, whether old books, magazine articles or on the Internet, I can not specify.