Randy Robinett only makes flat base bullets. But if they didn't work at 1,000 yards, Joel Pendergraft would have to give back about 50 of his IBS Marksmanship Points; Dave Tooley would have to give back his NBRSA single-group record & a bunch of IBS points, (me too, but a smaller number 'cause I have fewer,) and Jeff Rogers his Australian records. Etc. They work fine in up to a 13-twist barrel, iffy in a 14-twist. They'll shoot in a 10 twist as long as you don't push them over 3,150 or so, but you loose the theoretical advantage a slower twist gives.
Clinch River's are boattails, made on a secant ogive pattern; I have one 10-twist barrel that likes them better than the BIBs.
Brady Knight's bullets are on the same profile as the BIBs, a 10-caliber tangent ogive, but the 200s are boattails. For whatever reason, the three 12- & 13-twist barrels I've used prefer the BIBs to the Knight boattails (or anything else), but I've got two fresh .30 barrels this year, and for sure I'll give Brady's bullets a spin.
Charles Ellertson