Are nipples supposed to not be threaded for the first 4mm or so?

[Planet Indigo]

I received some nipples that are 13 mm height, and when I put the spokes through it, the first 4 or so millimeters don't catch any thread, only the last 7 or 8 mm of the nipples seem to be threaded.
Is that normal and common for all nipples?

 

[glennb]

Yes, normal. I imagine the reason is to provide strain relief for non-perpendicular spoke angles, as well as to help prevent cross threading by guiding the spoke.

 

[Planet Indigo]

Great, thank you for the speedy reply!