Wuff suggested this might be Vasart or Ysart Brothers.
Since the base is, I think, fire polished this is very unlikely to be from the Ysart Brothers period.
SophieB suggested early P7 Strathearn.
That would depend on the size of the weight - P7 was a "large" size (at least 2.7 inch diameter, according to Richard More's web pages).
Alan was "firmly with the late Vasart / early Strathearn option" and says he has "never known how to decide between the two."
For once, I almost completely agree with Alan.
Unless weights like this one have a label (Vasart, Pirelli or Strathearn) then it is hard to be sure about an ID. But if they have a ground out base finish then they are unlikely to be Strathearn.