RE: shooting issues
Throwing dirt on them is a sure sign of shooting a bit short. Sight in your rifle for 200 yds. and just aim at them where you want to hit. Very few shooters who can 'easily hit at 650 yds. would have any trouble hitting at 275 or even 375. To accomplish the easy hit at 650 takes some practice and you pretty much have to know where your gun shoots along the entire bullet path to do it regularly.
Unless you actually laser the range even fewer shooters can estimate range beyond 150 yds. or so. I see people try it all the time out on the prairie.