revdocdrew:

According to W.W. Greener, there is an attempt in making the barrel out of rods but to make the barrel to appear to be made from 1 rod viz.; "By tracing the twist, a confusion will be found to exist for about an eighth of an inch, every six or seven inches; and from this appearance you may conclude that, for a barrel so joined, the welder had not the best price."

This may account for some of the imperfections or perturbations.

Kind Regards,

Raimey
rse
rse