One Black Mamba was clocked at 17 klm's per hour over a very short distance of about 30 metres. This makes this species the fastest snake recorded. No way could it keep up with a horse, even at canter speed.
The Inland Taipan would be no where near the fastest striking or repeated striking snake. Overseas tests showed the African Puff Adder was the fastest striking snake tested, but since then the americans have been introduced to our Death Adders. These were found to strike 4 to 6 times faster then the Puff Adders in single or repeated strikes