The Firing Line Forums - View Single Post - Factoring in Barrel Length: 22" versus 24"

tom234 · April 13, 2008, 08:16 PM

The Lyman #47 manual says for a 2" change in barrel length the FPS change in the 2500 FPS range is 40 and 50 in the 3000 FPS range. Since all rifles shoot differently, aside from barrel length, you are always guessing unless you chronograph your loads. Elevation and temperature also change the equation as well.

April 13, 2008, 08:16 PM	#2
tom234 Senior Member Join Date: February 14, 2008 Location: Kansas Posts: 753	The Lyman #47 manual says for a 2" change in barrel length the FPS change in the 2500 FPS range is 40 and 50 in the 3000 FPS range. Since all rifles shoot differently, aside from barrel length, you are always guessing unless you chronograph your loads. Elevation and temperature also change the equation as well.