Rick L
Well-known member
choke is actually a relationship between the bore diameter and the constriction at the muzzle, a bore gauge that will measure both is the only way to tell other than the pattern board
if calipers measure the muzzle at 700 thousands - and the bore is a true 12 at .729 - you have a full choke
if the muzzle on that gun measured .710 you would have modified
it is not rare for a gun to be backbored- so-
if the gun is backbored to -let say .740 -- that .710 would be full - i have been told guns were modified or even more open that are in fact extra full - the waterfowl doubles were often backbored and the chokes deceiving, My LC Smith longrange was measured as light mod at the muzzle by the seller but is in fact extra full with 42 thousands choke
so- unless you have a bore gauge - the pattern board is the way to tell what you have
if calipers measure the muzzle at 700 thousands - and the bore is a true 12 at .729 - you have a full choke
if the muzzle on that gun measured .710 you would have modified
it is not rare for a gun to be backbored- so-
if the gun is backbored to -let say .740 -- that .710 would be full - i have been told guns were modified or even more open that are in fact extra full - the waterfowl doubles were often backbored and the chokes deceiving, My LC Smith longrange was measured as light mod at the muzzle by the seller but is in fact extra full with 42 thousands choke
so- unless you have a bore gauge - the pattern board is the way to tell what you have