As answered in the PM, it's an oversight but something I may fix if/when I return to working on this. A few ideas floating around as a hotfix: either give a penalty for the weapons that do this (-1 per 2 rounds missing from the 10) or make the guns semi-automatic and give them the Rapid-fire feature.
If possible, I'd like this thread not locked due to necromancy, as though while I'm still not entirely active on working on this, I'm still highly interested and invested in answering any questions and would eventually like to return to it.