Okay done to death but ..... ;-)
Success! ... I hope? I'm really pleased with how this one came out . :-) Many thanks everyone for your comments and advice and thanks for looking.
I used a sound trigger which was tripped by the pistol firing. By changing the distance between the microphone and gun I was able to change the delay from pistol fire to trip the 580EX which was set at 1/128 power to give the shortest duration. Camera was EOS50D with EF180L macro lens, ISO 320, 2 second exposure, F9. A reflector was also used to kill some shadow!