Yep, no .455. This conversion was so popular, it is hard to find a 455 Webley in original condition. Unfortunately, 45acp bullets are 0.452 in diameter, and most converted guns are not renowned for their accuracy.
I shoot 45 autorim in mine, so if you need some full moon clips, I can send you a couple I'm not using. Just PM me with you address, and I'll stick 2 or three in an envelope.