I have been shooting my remington SFS 300 RUM now for a few years. I have only shot it up in colorado and down here in texas a few times and it has performed very well. But, I would like to set it up to shoot further. It currently has a 4-12x56 zeiss scope with a 30mm tube. It shoots fine with 180gr remington factory ammo, but i have only shot it out to about 200yrds. What do i need to do to get out there to 400-800 yrds? Am i allready setup for that? Do i need to change to a hotter ammo? Help me out, I am basically a whitetail hunter from south texas that journeys up north every once in awhile but i would like to someday feel confident out to some greater distances. thanks