Paint mystery

Hmmmmm, a strange thing has happened with the last 3 bodies I've painted. I bought some truck van and SUV paint at canadian tire when it was on sale. I bought red and gunmetal and decided on color based on the lid. Well when I painted the lightning and the ferrari, both colors sprayed on much darker than what was on the lid. Both colors came in big spray canisters and on the gunmetal one, I finished the canister due to many coats of paint, but it always stayed very dark, almost identical to the paint job I gave my 3000gt (charcoal)

Anyway, so I was in Walmart the other day, and I thought I'd try the duplicolor paint there, so I got a big can of a bright met blue truck van and SUV paint for my 70 mustang mach 1. I started painting it a couple days ago. When i put the first coat on, it was extremely dark, almost a black-blue!!!! I've been putting coats on ever since, and just when I was putting on the last coat, it started to spray out exactly the correct color that's on the lid!!!! Luckily I had enough left to get everything covered in the correct color (it looks awesome BTW) I'll be sure to pile on the clear coat, as I don't want to be polishing through the bright blue to the dark stuff :D

So WTF is going on!? I've never noticed this with regular automotive lacquers (the direct match ones from the smaller canisters) I just don't get it. Any ideas people????

My guess is the metallic particles weren't escaping the can evenly, therefor you were getting more of the base paint which would be darker. For example: Sometimes painting with metallics with an air brush you really have to open the nozzle up to get the particles through there.