http://www.navweaps.com/Weapons/WNBR_525-50_mk1.php Navweapons site, QF Mark I] In comparison, the French  138 mm Mle 1934 guns as used on the Mogadors had a maximum range of 21,872 yards (20,000 m) at 30 degrees with an 88 lb (39.9 kg) SAP shell. [