Old .22 hornet, rough date

Recently metal detecting found an old .22 hornet made by Kynoch. At this particular spot I have found bullets from 1916 all the way to 1962.

I was wondering am apoximate date on this shell as some small details differ from a new age hornet, such as the thickness of the red, and there is no small lip above the rim.

Any information is appreciated, cheers Hamish