The problem with everything pre-SAAMI (mid 20's) was a lack of standardization. But after SAAMI came on the scene--and there were a whole lot of short shells and short-chambered guns produced after that--there were different proof standards for guns with short chambers vs those with the "modern" 2 3/4" chambers. And it was about that time that the ammo makers started putting two warnings on their shell boxes: 1. Don't use long shells in short chambers; and 2. Don't shoot smokeless powder loads in Damascus guns. There's a lot of information left out of those warnings, but they are an example of erring on the side of caution.
