There might be pitting in the bore (typically due to insufficient cleaning after using corrosive ammo), or it could be because a coating such as Amelon MicroSlick was applied to it. The first scenario is a much more common occurrence.
The bore of a gun relates to the diameter of the hole in the barrel - and in turn the diameter of the bullet the gun can fire.
The bore is the inside of the barrel- that is, the hole that the bullet is fired through. The diameter of the bore is measuring how wide the bore is from one side to another.
Diameter of either the cartridge or the bore, dependent on how the measurements are taken.
get a bore attachment to a screw gun or drill.
The word "caliber" refers to the diameter of the internal bore of a gun or firearm barrel.
What are you asking?
bore diameter
The bore refers to the hole in the gun barrel thru which the projectile (bullet) passes. Some guns have a smooth bore, but many modern guns, both pistols and especially rifles, have a rifled bore, that is, the bore has a helical (spiral) groove that causes the projectile to spin as it flies thru the air. The diameter of the gun's bore determines the size of the bullet or shell (e.g. .22, .45, 9mm, etc.)
The range is not directly related to bore diameter. And the largest gun over built (The Tsar bombard) has a 36" bore.
Caliber is a word used to describe the bore diameter of a gun. It is also informally used as a synonym to grade or rank.
It depends on the caliber of the bullet.
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