A chap stopped by recently and the conversation focused on stretched barrels. Many years ago, it was not uncommon to cut off a section of barrel to shorten the firearm. Stretching is simply our term for reapplying a section of barrel to recreate what we think the original looked like.
There's nothing wrong with this, it is just that some of us type-A's want to know what we are looking at. Some of the work being done today is exceptional, and the finished guns most handsome. An adaptation of the old joke, I have nothing against stretched barrels, some of my best friends own some. This is a specialty job that I, myself, would not do. My welding is limited to very heavy equipment where finished aesthetics were the least of our concern. I would defer this job to specialists, then build around their work.
But how to tell? First, a slim-diameter bore light is useful in many cases. On good work, the informed collector just can't tell from the exterior. That is what makes it acceptable work. In addition, I carry a .30 cal ball in my pocket. By rolling the ball down the barrel slowly at a modest tilt, you will often hear a distinct "bump" when the ball rolls over the joint. It is hard to get this seam to fit perfectly. Oftentimes, you will hear two distinct bumps, as the added tube was done in around the middle, so that when the observer looks at the muzzle and possible rifling, he is seeing real, old material out there.
Also, underscoring the obvious, in cases where you see a signature real close to the breech plug, it very well may be an indicator of removed barrel at the breech end.
