Originally Posted By: gunman
If you have two tubes of equal diameter and lay them on a surface table the they will be on a horizontal plain .Gun barrels are put together so that they are parallel in the same way . It is so when you look down them one tube does not stand higher than the other .

Well yeah Sure, I'm not a Gunmaker of long years experience but have basically realised this ever since I owned my first SxS back in 1955. Quite obviously one doesn't want one of the barrels pointing up toward the Sy & the other Down toward mother earth. This is so elementary is not really worthy of mentioning. What may not be so obvious to some but should be if one uses any power of observation is that the two barrels "Converge" from breech to muzzle, All The Way Down. That my Friend is where the "Regulation" occurs. Even if they were calculated out where to sit & so set at their original assembly with no further adjustment made to them they were regulated. Admittedly some guns get more care in this regulating than others & hence are apt to "Shoot Together". As stated earlier by another poster barrel regulation & choke regulation are entirely two different matters. Both can be done with great care & consideration or both can be done on a Hit or Miss basis. A "Good Gun" doesn't just have the barrels thrown up there & soldered in where ever they happen to land.

Miller/TN
I Didn't Say Everything I Said, Yogi Berra