It depends on specifically which model you have. I do not have a Bisley, but do have several other single action Ruger models--so from a strength point of view Bisley or not doesn't matter. With Ruger, the frame size rules all. If you have the Blackhawk or, sharing the same frame, "original"/old large frame Vaquero Bisley, then yes, it can be loaded "hot" as anything the Redhawk/Super Redhawk can handle. If it's the New Vaquero Bisley, then no -- it's built on the basic same smaller "mid frame" as all New Vaqueros and recent year 50th Anniversary.357, or .44 Special and .45 Colt flattops (but not the larger cylinder-framed 50th Anniversary .44 Mag). Frame size governs what diameter cylinder size and hence chamber spacing. The midframes are still robust guns but just don't have the room for the larger model's cylinder and hence beef 'tween the chambers to withstand super hot - aka "Ruger Only" or "magnum- level" loads. (We're talking strictly .45s here. .357s are fine with either frame.) Which model/frame do you have?