Modern Warfare 2 Pit Boss Achievement/trophy

Thanks so much i have been struggling with this and i done it second attempt after watching this (because i stupidly picked up a desert eagle!) 5 stars!

My pit time is 26.3 secs, but i want to beat IW time of 22.6. Anyone know how the hell i can shave 4secs off. I use the MP5K Holographic with the m9, i never reload, i just switch to the M9 while i jump down off the roof. Any real suggestions by some pro pro players out there will be much appreciated???????

dude i watched this and after i got 28.3 secs strait away :D thanks!

FANTSTIC! I done exaclty what you done and t the same time! ^_^ 5/5 cause it worked!

@xxEvilDavidxx look at my one my aiming rockss ^_^

but the trophy says 30 seconds or under ??

u got 29.9 sec nicee

i have tried this millions of times and i cant beat 35 seconds :(

pissing me off this i got 30.5 as my time before i nearly hulk samashed my pad cos of it !!!

it works