Matthew Poole and continuators on Judges 20:16

16 Among all this people, there were seven hundred chosen men left▪ handed , every one could sling stones at an hairs breadth, and not miss .

Heb. shut up on their right hand, i. e. using their left hand instead of their right.

An Hyperbolical expression, signifying, that they could do this with great exactness. There are many Parallel Instances in Historians of Persons that could throw Stones, or shoot Arrows with great certainty, so as seldom or never to miss. Of which see my Latin Synopsis. And this was very considerable, and one ground of the Benjamites confidence, because in those times they had no Guns.

Marginal references: Chap. 3. 15.