Let’s not make it sound like double-base rifle powders are dangerous. They are not. The Hi-Vel numbers contained only about 10% to 15% nitroglycerine, no different than some of the early DuPont powders used for years in the Cal .30 ammunition. British Cordite contains an even greater percentage of nitro, as much as 50% in some applications. Even Ball or Spherical powders contain some nitro.
The reason that the double base powders, like Hi Vel, didn’t stay around long was because they were corrosive.
Internet stories about the dangers of smokeless powders never cease to amaze me. There was one recently, on another forum, where a guy encountered some badly corroded 30-40 GI cartridges. He pulled a couple of bullets and proclaimed that he had found the reason. He swore that the powder was a bright red color, glowed in the dark, and was a disaster about to happen. To my eyes, the old Peyton powder was still as fresh as the day it was made. I replied that Peyton powder was always a bright orange color and the corrosion was on the outside of the case, not inside, and was the result of improper storage. Needless to say, he never replied, but the seeds of alarm had been sown.