Just seems curious. Are there any Shells prior or post 1975?
Like most things to do with Dunhill nomenclature, any discussion of the use or omission of the word Briar pretty quickly gets both numbingly complicated and appears to involve at least some inconsistency.
What is apparently straightforward is both "Shell" and "Shell Briar" were both in use from 1917 to the early 1930s. And according to Loring, "Shell Briar" was used whenever "Made in England" was omitted. (After 1935 "Made in England" was always used.)
The crucial change that does yield useful information (for instantly ball parking whether a pipe was made before or after the 1930s) was the nomenclature of pre-1930s pipes used quotation marks around the words Shell or Shell Briar, and a possessive with the brand name Dunhill.
As for when the word Briar got revived--my guess is that it happened when patent stamps were phased out and the group size (in a circle was added). I own two virtually identical Dunhill 56 bents: the 1949 omits the word Briar, the 1952 includes it. (And the same usage hold true with a pair of 120s I have from 1950 and 1955.)
As for pipes made after the 1960s with nomenclature that omits the word "Briar"--a good question. A wild guess would be only if an individual pipe didn't have enough smooth space. But on this, I'll have to defer to others here with more experience of shells made from the 1970s on (especially smaller models).
