It's the length around a round object, like if you would run a tape measure around barrel or a ball.
no
Over a Barrel: helpless, at a disadvantage
Run brushes through it, then run swaps through it.
Three bars
Ensure the firearm is unloaded and clear, get a cleaning rod and a bore brush, and run it through the barrel.
What does J1727 on the barrel of my 270 mean?
Do you mean you have an extra barrel, or are you calling the tube magazine below the barrel another barrel?
In the 18s
The barrel has deep grooves milled into the outside of the barrel. Called flutes, the grooves reduce the weight of the barrel, yet leave it a stiff barrel with very good accuracy.
slap its behind then it will run faster or feed it more or sell it for a faster one
There are many different barrels. Specify which you mean