I have a large number of cartridges at a historic mine site in southern New Mexico. The primary occupation of the site is from around 1903 to 1911. These cartridges are of a very wide variety of calibers. they were all identifiable 30-30, 30-06, 44-70, 45, etc. The question concerns their treatment. Virtually every one of them was found crimped in almost exactly the same place on the cartidge. Anyone have any idea what this behavior is?