The Scammell Pioneer R100 was a British heavy truck used as an artillery tractor for medium and heavy artillery. Medium artillery pieces included the 60 pounder, 6" Howitzer and even the 4.5" and 5.5" Howitzers. Heavy artillery towed included the BL 6" gun, 8" Howitzer, 155mm Long Tom and the 7.2" Howitzer. Scammell produced 980 Pioneer R100 by the end of WWII although by 1943 they were joined by Albion CX22S tractors.