there was a good archeological documentary i saw on PBS that examined the sight. using physical evidece including test firing of the kinds of rifles they where using.
what the Zulus did
1. they took this hallucinagenic, that provoked temporary fearlessness and instilled in the warriors a feeling of invincibility. it came from a root that is local to the region. it was a comon tactic used by the zulu tribes
2. i forget what they called it but they used this tactic where there was the main force and a smaller force wiith the fastest runners. the smaller force would run up on the british line from the flank and draw their fire. the british perhaps thinking it was a small raid or something. it was all in the timing and the main force was almost on top of the before the british realized what was happening. by the time the rest of the camp was alerted the perimeter had already been over run causing complete chaos with the british defenses
3. they attacked right before dawn while it was still dark limitig the sight range of the british riflemen (obviously the zulus were no dummies)
what the british did wrong
1. the british comander of the camp had extended the perimeter too far so that the rifle men in the perimeter line weren't close enough together to be effective against a huge onslaught due most likely to over confidence etc. etc. the archeologist could tell because of the spacing of the casing groupings that were dug up. this appeared to be the most relevant factor
2. the rifles the british where using tended to jam up if fired too often in rapid succession...like one part of it would heat up. the guy demonstrated it in controled setting and got off maybe ten shots firing as fast as he could (bolt action) before it heated up and jammed. plus those rifles tended to produce alot of smoke making it more dificult to see after so many shots were fired.
it was simply a matter of a well planed surprise attack vs an overconfident underprepared british force
~json