Board Thread:General Discussion/@comment-25349112-20140826000717/@comment-25396609-20160127201841

Ruby herself is fairly light in build and short, Crescent Rose (assuming lightest possible materials) weighs probably in the area of 20-40 pounds.

Speaking from experience, a .45 caliber handgun has enough force to send a full grown man backwards a solid foot, a .50 caliber rifle has vastly more kick behind it and it is being fired by someone (maybe) half the size of that which can be knocked backwards by a handgun, and is likely utilziing high pressure rounds on top of it, then you factor in her semblance which both acts as a springboard and allows her to move faster, and a .50 cal rifle is plenty enough to launch her aroud.