Hi Lee,
I have exactly the same powder, same jug, same everything and I bought that powder the same time you bought yours. As for shelf life, I'm not sure but I can tell you I still shoot the stuff with no problems. A couple of us old farts bought a case of the stuff back then when I was heavy into bench rest shooting. I also have an empty one pound canister of H322 marked,
U.S. GOV'T Surplus
Sug. Retail $7.99 and the sticker on top of the lid says I paid $5.99 a pound.
Dave T
Dick had my Scot's 322 and my old 2015BR.
I think it was around 1980 that we imported some Scottish powder from the Nobel's factory down to South Australia. It arrived in 20kg tins marked Nobels Neonite. Well, we thought they had sent the wrong stuff, but no, it was the real thing - H322.
I recall that it burned a bit hotter than what we have now - I think we used to load around 27.8gns.
At the time we only had access to DuPont and Winchester powders Down Under, and this H322 created a bit of a stir.
Very accurate and higher velocities than we were used to as well.
Brendan Atkinson