On dating of the late roman helmets.

[Virilis]

Hi all!

After shamelessly hijacking the thread concerning Deepeeka´s improvement on their late roman swords, I decided to start a new thread about the dating of the late roman helmets. I will try to reconstruct a timeline when these helmets probably were in use. I will depict this broad outline with the help of some of the most famous finds concerning late roman helmets (based on Bishop & Coulston, James, Klumbach, Miks, Travis etc.) I would also like to hear your opinions on this. I will start at the end of the 3th c. AD.

-280-320 AD: Deir el Medineh helmet & Oudheden, Leiden spangenhelm.
-300-400 AD: Berkasovo, Deurne, Budapest, Augsburg-Pfrsee, Burgh castle, Heteny helmet (mainly stretching the timeline to 400 AD
-400-450 AD: Concesti helmet.
-300-500 AD: Intercisa style helmets, Richborough helmets (the long continued use is based on the pictorial evidence on mosaics etc.)
-400-600 AD: spangenhelms like Baldenheim etc.

I know this is a controversial subject but are the basic elements right and have I missed something important?