SCG,

Those necks can be a real pain, and a big disappointment when having shelled out serious money for a quality (debatable in this case) genetic neck.

If the stems of the hackles do not play ball, it may be time to change the pitch.

On a hard surface, even a level hard surface, they may (will) flip and end up as you described.

Try a slender bed of a softer material, such as a skinny layer of dubbing, and you may find these feathers behaving much nicer.

Cheers,
Hans W