T. O'Heir,
There are two effects:
First effect: in his book, Rifle Accuracy Facts, Harold Vaughn, former Head Aeroballistician for Sandia National Laboratories in the U.S., filed 2° slants on the bases of some .270 Winchester bullets and showed they were responsible for about 0.8" of radius of dispersion at 100 yards (a 1.6" average diameter group). He found slanting soft points at 45° on the same size bullets causes a radius of dispersion of 0.135", or a 0.27" group diameter. So it's not zero effect, it's just too small for most people to notice their average group opening up. Unless you were shooting bugholes from the bench, you wouldn't see it, because group size contributions don't add linearly. To add linearly, all sources of error would have to be in the same direction at the same time for every shot, but they aren't. Sometimes they subtract from the direction another source of error is going, and mostly they are off at an angle between those two extremes. This causes error sources to add the way standard deviations do: as the square root of the sum of their squares.
So, if you have a .270 Winchester shooting Vaughn's bullets into 1" at 100 yards, then you let the feed ramp start hammering the soft points so they get a 45° flat across them, the resulting combined error source group size in inches will be: √(1²+0.27²)=1.038". That's so much less than the variation most people get in their groups at that range that they may be excused for thinking the slant on the nose has no measurable effect. It actually can be measured, but only with very precise bughole benchrest guns.
Second effect: (This is the reason meplat uniforming trimmers and Whidden pointing dies sell, and why Nosler has just introduced a match bullet with the smallest meplat diameter made.) Smashing that blunt slant into the nose of the bullet reduces its ballistic coefficient by giving it a more blunt, less aerodynamic tip shape. The average shooter firing with hunting accuracy at 300 yards or less doesn't normally notice the effect of this, but long-range target shooters see the change in bullet drop. Even with undeformed noses, hollow point match bullets have enough tip variation to cause several inches difference in drop at 1000 yards. Bryan Litz has information on this at his site, IIRC, and in his books for certain.
