Hello, ag05. You might check with Buffalo Arms Co., they have hard to find brass & dies. If I am not mistaken, the bullet for the .44 Webley was either
"heeled"..like a .22 L.R., the bullet was same dia. as case, with a short shank, or heel fitting inside case, or, They were hollow-base. I would slug that bore to make sure..If this is the case...any bullet you could fit inside a case would be undersize & fall through bore. Best of luck!