The maker’s mark “BW” is very rare and there is no real certainty over whose it is.  From a study of Grimwade, there are the following possibilities:

Bowyer Walker was a large-worker with a mark registered on 10^th April 1735.  He is also recorded by Heal as a Plate-worker.  These sugar tongs are unlikely to be by him as their earliest date is 1785, 50 years after he registered his mark and he was a large-worker.

Benjamin West registered his mark on 14^th January 1738, again as a large-worker.  It is also unlikely to be him for the same reasons as above.

Brook Walker registered marks as a buckle-maker in 1779 and 1788.  His marks are recorded as being in a rectangular punch with cut corners.

Benjamin Wilson registered marks as a buckle-maker in 1785 and 1787.  His marks were in a rectangular punch without cut corners.

From this logic, it would seem the most likely maker of these tongs, dated between July 1785 and May 1791, are by Benjamin Wilson.