I can not speak for the US industry but the UK industry moved from dovetail to chopperlump due to two forces, cost and craftsmen.
Before the wars, dovetail lump was the cheap version as the material rather than the labour was the expensive item. Dovetail used two relatively cheap plain tubes plus a lump which were then brought together by skilled craftsmen who were also relatively cheap.
Chopperlump barrels required much more expensive blanks to be machined and hand fitted by the same craftsmen. The labour costs were rather less, not so the materials, which made this a feature of expensive guns for the discerning.
As chopperlump barrels became cheaper (economies of scale), more and more barrels could be made that way until they challenged the dominance of dovetail lump barrels.
As the dominance of dovetail barrels diminished, so did the number of craftsmen who were willing and able to produce them.
I have read that by the 1950's they were a dying breed and sometime in the 1960's & 70's they effectively died out which left the field of battle to the chopperlump unopposed.
I would guess that the US manufacturers simply demonstrated 'manufacturing inertia'. Given the emphasis on mechanised production, they were less effected by the loss of a section of the workforce through retirement so why change something that you are tooled up for and works just fine?
Last edited by Toby Barclay; 08/23/20 01:51 PM.
