It has been my experience that flat base bullets shoot tighter groups at 300yds or less. VLD's and other boat tails "start" to come in for me at 300yds. When I put my 260Rem together I wanted to shoot Berger 140grn VLD's. But I also got some Rem PSP"s, 140grn, to use for break in, sight in, load development, etc. They are flat base and "bore riders", the only such bullet that I know of ? Anyway, shooting at 200yds or less, I "could not" get the Berger's to group as well as the Remington's, even with a 1 in 8 twist barrel. It wasn't until I started shooting at 300yds that the Berger's started to tighten up. I have heard it said that boat tails have to "go to sleep"?? Good Shooting..Jim