Depends largely on the style of the bed.....and what you mean by "wrapped brass".

Lindac, the antiques dealer told me that it wasn't solid brass. I think it's an iron core that has been literally wrapped with a sheet of brass. By 'style' I guess you mean pattern/design? I'm not finding any on-line that look similar enough to point at. Will try to get some photos... Thanks!

All "brass" beds are wrapped.....brass is not structurally strong enough to hold the weight of a bed without a core of iron or steel. Wrapped is different from brass plated.
A picture would help. I was at an auction the middle of the summer that had a brass bed that went for a surprisingly small amount to me....only about $250.

There's also spun brass used to make seamless cylinders that fit over the iron structural pieces. I don't know when the technique changed - or maybe there were always 2 methods - but that's how they were made in the 1970's by a local custom manufacturer when brass beds regained popularity.