It's difficult for me to make clear this part of bullet.
I use cylinder with 16 vertices, add 2 horizontal loops "ctrl+r", insert "i" 2x loops. Then I extrude with individual origins and normal transform orientation polygons
Then I add subdivision surface and some loops to save form. But there are problem with entrance 5 edges in vertices and bad form of curve shape
How to save curve shape of cylinder with such deformations and to get it with clear topology?
LukeD, thanks for solution to the problem. Here's my result: