Collocations for barrel - noun

beer, whisky/whiskey, wine, etc.
oak, wooden

fill
They filled the barrels with cider.

contain sth

a barrel, per barrel
The price of oil had fallen to $16 per barrel.

by the barrel
Beer is sold by the barrel.

barrel of
a barrel of oil

gun, rifle, shotgun
I felt the gun barrel at my head.

rifled
7.5-inch, 26-inch, etc.

look down, peer down
She found herself looking down the barrel of a gun.

point

the barrel of a gun