I was given a straight 20rd at mag today by a coworker who was enlisted shortly after Vietnam. Guy was in army for 8 and then Air Force for 20 before retiring, and has been at his current job for 20, and he is a good friend. The mag is a Simmonds / Universal 20rd straight mag typical of the style used “back in the day” and it is loaded with blanks of roughly the same vintage. Before I get wild and start using this mag, is there anything I need to consider? I know 20rd curved mags are supposedly more reliable, and the followers have changed a bunch, and some of the older mags are a bit more collectible, so should I move this thing around and put it with a vintage rifle through trade or should I just use it like I do any mag?