With the right bullets , 115's , the 243 is a 12 - 1300 yd gun . The 115's have to use a faster than standard twist barrel , 1 - 8 IIRC , to get them to fly . Even with the 105 - 107 ' s the caliber will work out to 1K easily .

The stuff that I typicaly shoot , steel plate field courses , the target needs to move so the spotter can call the hit most of the times . With the 6mm's even the heavy bullets sometimes make calling a hit hard even for experienced spotters . Shooting paper it wont matter though .

Lots of info at these links ,
http://demigodllc.com/articles/pract...ing-equipment/

http://demigodllc.com/articles/pract...ooting-optics/

http://demigodllc.com/articles/pract...ting-shooting/

Stuff to shoot ,
http://sportingriflematch.com/

http://www.co-ar15.com/forums/showthread.php?t=37424

http://www.co-ar15.com/forums/showthread.php?t=6763