That would be news to me. I do not shoot much jacketed nor hard lead but not for that reason. Bullet jackets and lead, no matter how hard, is still softer than steel. I don’t use them because it is easier to develop an accurate, non leading load with soft lead bullets. The only exception is my 1917s. The rifling in those barrels requires jacketed bullets or lead bullets cast from a harder alloy, I use 16/1, lead/tin.