crl:
While most of us on this forum would love to revisit the 'vintage years', the one draw-back would be cordite! It has been the ruin of many a fine gun, and no-one I know would even think of using it in a favourite gun or a double.

Basically, it is a double-based propellant, containing nitro-glycerine as well as nitro-cellulose, but has no retardant coating so it burns very hot, far hotter than modern powders. The outcome is generally severe throat erosion in firearms that have been used a lot, and the occasional deep gas-cut in the chamber or breech-face if ever a primer leaked or a case cracked.

The only source of cordite today (that I know of) is to tip it out of old Brit mil-surp .303 cartridges! My advice would be to forget it! There are a number of very good modern substitutes for cordite that burn cooler, cleaner, and generate lower pressures for the same ballistics.