An Iowa chain with more than 300 gas stations will grow a little bigger. Kum-n-Go already operates in a dozen states, with 305 convenience stores of the Krause Gentle corporation. The chain will buy a dozen southeast Iowa Home Oil convenience stores in towns including Ottumwa, Fairfield and Burlington. Both companies say outside of a change in the signs, nothing will change in the operation of the convenience stores. Home Oil says it’s spinning off the 12 stations to focus on its “short-Stop” line of stores in high-traffic locations and major interstates, including existing convenience stores in Des Moines and Cedar Rapids. Carpenters Companies, owner of Home Oil, also runs ProLube oil change centers and G-N-F, a trucking company.