 Most infantry divisions in the North African Campaign deployed a " cannon company " equipped with six T30s and two 105 mm <unk> HMCs . In one encounter in North Africa , the T30 was used in an attempt to destroy German tanks . Although the T30s fired several <unk> , the German tanks were barely damaged and the T30s were ordered to retreat under the cover of smoke to prevent losses . After several similar experiences , U.S. forces ceased the practice of employing self @-@ propelled howitzers or mortars in direct combat with tanks . 
