We hear a lot of idioms and phrases involving BARREL.
The Link in "thefreedictionary.com" shows a lot of idioms using "barrel" as a noun and a verb.
"Barrel" is defined in Merriam-Webster as a noun:
a round usually wooden container with curved sides and flat ends.
the amount of something in a barrel.
the part of a gun that the bullets go through when the gun is fired.
One thing very interesting to me is when you use "hit someone with both barrels", it is not very difficult to understand what it means and that the third definition is used. But, why they use "both" and "barrel" together. Why just two? Isn't it the more, the better and stronger?
Would it sound weird if someone says, "Hit someone with three/four or even five barrels"?
Best Answer
The reference is to a "double-barrel shotgun". Though there are firearms with more barrels, they're rare.
Further, the double-barrel shotgun often has two triggers, one positioned slightly behind the other, such that if one pulls hard enough both barrels will fire in quick succession, producing a devastating blast.