Jim Legg,
Yes I am a Brit, but more importantly I am English and from the Premier County located in Central England.The County where it is a proven fact that King Arthur REALLY had his Court, where Excalibar was pulled from the Lake.Where the first battle was fought in the Civil War ( Battle of Shrewsbury) where guns were first used in War against the Bowmen.Proud Salopian. Ha Ha.
Quarter Cylinder is usually expressed as 25 thou of constriction on a 0.729" Bore (12) and improved cylinder is usually 0.005" constriction.But those constrictions as we know does not necessarily throw the correct percentages.
Anyway stop bickering and obey your King.
"Guards off with their heads "