If you hold any weapon in your hands without a magazine, looking at a corresponding magazine in front of you and your inventory has no place for the magazine, you still get the option 'Take' as well as the option 'Load weapon'.
'Load weapon' option works as intended (I suppose) but if you press 'Take', the magazine is put into the weapon as if you pressed 'Load weapon' but without any animations or delay whatsoever.

Version 0.63.146624