 A U.S. Army study in 1945 concluded that only 10–15 percent of wet stowage Shermans burned when penetrated, compared to 60–80 percent of the older dry-stowage Shermans.At first, a partial remedy to ammunition fires in the M4 was found in 1943 by welding appliqué armor plates to the sponson sides over the ammunition stowage bins, though there was doubt that these had any effect.Later models moved ammunition stowage to the hull floor, with water jackets surrounding each stowage bin.