[Loading rocket types]

Hmmm, I've tried it on more than one occasion and the same thing happens, but it's all been in the same game. maybe I'll try starting a new playthrough and see if it continues.

[Loading rocket types]

Ok, this is a total n00b question, but I can't seem to figure out how to load stun rockets into my rocket launchers. I've tried dragging them onto the launcher in the inventory, I've tried putting them in the character's belt and reloading from there, but it doesn't work. My soldiers have enough TUs, and can reload regular rockets perfectly fine, but simply refuse to load the gas ones. Is there something I'm missing, or is this a bug?