Just wondered if any of you guys use a .243 ack imp ? and if so how does it perform when out varminting and out to what range can you still be affective? i use it on all the species of deer here to great effect although the nearest things we have to ground hogs are rabbits, so i admit i am partial to the odd 300yd bunny!

243 AI is a great round. A friend in Tennessee allowed me to fire his converted Winchester M70 Heavy Varmint. It has a new custom stainless 30" barrel with a compensator and VXIII Leupold. The first time I fired it off of bags I fired a .263" (.668 cm) five shot group.
It is an "AI" conversion that I would recomend at barrel change time.