Several years ago Remington printed some ballistic figures for calculating how much velocity was lost cutting back a barrel. I believe they took bore size and starting velocity out of a 24" barrel as standards. If I remember correctly loss per inch was very little from a 45 caliber barrel. They no longer publish this information where they used to. I am incorrect in as much as they use the velocity rather than the bore. It was published by Remington and is from their Centerfire Rifle Ballistics Tabel Information I printed from
http://www.remington.com/ammo/ballistics/tableinfo.htm on Oct4,2003. for a rifle with 2000-2500FPS out of a 24" barrel you lose 10FPS for every inch cut below 24". 2500-3000FPS 20FPS loss. 3000-3500 30FPS. 3500-4000FPS 40FPS. I would assume Remington would not publish such information unless they were fairly confident of it's accuracy.
