Idiom meaning to face a painful…

Idiom meaning to face a painful, difficult or unpleasant situation with courage and stop putting off the inevitable. It is commonly said to come from battlefield surgery before anaesthetics were available, when wounded soldiers were given a lead musket ball to clench between their teeth to endure the pain. Rudyard Kipling used the expression in his 1891 novel The Light That Failed. A related phrase is grin and bear it.

The answer in 13 letters