What is the use of the barrel shown in the picture? It often comes with cheap housings. On one side the 5mm housing can go into it and on the other side it is quite narrow so that only cable can pass through it.
Can it be used to make an improvised cable stop to install V-brakes on a bike without a cable stop -- something like this Hardrock? It can be inserted into the rear of the cable collar.
Of course a better solution is a clamp-on cable stop by IRD or Origin 8.


Barrel that comes with many cheap brake housings like Jagwire Basics of XLC