There are some impressive photos out on the net somewhere. Mostly the ones I have seen over the years were related to pointed bullets. (Maybe all of them were, I don't recall all of them.)
I wasn't trying to suggest you do anything improperly, it's just that your question doesn't seem to have an absolute answer.
As I said earlier, I've asked the question but received varying responses. The reason I asked is that some .457 bullets I've seen seem to have a small flat meplat. I'd just as soon I didn't blow up a tubular magazine also.
Also, at least one blown up tube magazine I recall was not related to a pointed bullet, but had flat point bullets and a protruding primer. (as seen on some other reloads).
