On Thu, 14 Sep 2017 18:52:14 +0100, T i m wrote:

snip

I just got a reply from an eBay seller who has measured the barrel
they are selling and their measurements are at the end of mine in
square brackets:

55.5 mm long (including the nut). [57.4]
(I think there is supposed to be a small crimp on the end that mine is
now missing, hence the difference).

8.6 mm outside diameter of tube. [9.2]
(This could be the larger diameter to take the larger filament you
mentioned Chris?)

7.9 mm inside diameter of tube. [8.6]
(Same again)

12 mm across the flats of the nut. [12mm]
(Ok, so that hasn't changed.)

8.6 mm inside diameter of the thread. [8.6] mm
(And that's the same, suggesting the flange on the nut might be a bit
thinner bit the actual thread spec the same)?

So, I could get this one and then it would take the newer filament
later if required?

Cheers, T i m