6.5 x 50 R AND 7.7 x 58 Arisaka Dummies

I have the 6.5 x 50 and 7.7 x 58 Rimless Arisaka dummy cartridges with 2 knerled rings on the case. They are the same as described by Elks in “Japanese Ammunition 1880-1945” with one difference. Both of mine have brass jacketed lead core bullets instead of the hollow bullets Elks describes.

Are these a later model or are they something different than what Elks is referring to?