Q: I have a brief question. I am often seeing mention of some different kind of ogive with regard to certain bullets. What part of the bullet is the ogive? Does it have an effect on drag?
Kenneth Reeves
A: The ogive is the curve between the bearing surface and the point. The radius of the curve, which is usually given in respect to the calibre, ties the picture together in the proper relationship. The ogival radius has significance only as it relates to bullet diameter.
The centre point of the radius is also important as it controls the length and helps define the shape of the bullet.
If it has a tangent ogive, the centre point of the four-calibre radius is at right angles to the cylindrical bearing surface and opposite the intersection between that surface and the curved ogive.
The secant ogive has the centre point of the eight-calibre radius lower and opposite a point on the cylindrical bearing surface. This gives a higher ballistic coefficient and usually retains a decent bearing area.
The ogive can be straight, parabolic or circular and the difference in drag will be very small.
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