I first bought a bar .270 and a tasco world class bdc scope after I got out of the military in 1987. I shoot lefty, so the semi-auto works perfect plus I dont have to take my eyes off the target. So thats why I ordered the bar 300. The new models come with an adj. brake (not sure how to adj. that). I have to wait for them to build it. Cant wait to get it. Please be gentle, but I have a p1 shepard scope have had it for some time now. So thats where Im confused. I have been on so many ballistic drop sites trying to match the bullets to the scope It has mad me totaly lost. The drop figures in inches for the scope is(just to name a few) -49.00 at 600,-172.46 at 800 and-320.9 at 1000yds. cant seem to figure the right hold over, versus the bullet bc and velocity. Didnt think it would be this complicated. Any help would be greatly aprieciated.