[Wiffles]

The 50's gun they had was huge and prolly emitted radiation due to its reactor. Glados made the new version though. But yeah it seems dumb for APERTURE to not release it back then... maybe they were looking to refine the design further?

I never really thought how much they retconned the old story of Portal gun being invented after Cave's death. Absolutely makes no business sense, the again Aperture science never made any sense