I didn't measure mine when I made it, I simply started sawing off sections until it felt the way I wanted it to. As it turned out that was 20 1/2 ".
I still get an honest 2050fps from most factory ammo and over 2150 from some others and my handholds.

As the late gun writer and African PH Finn Aagaard once pointed " a 500 gr .458 caliber bullet moving at 2000 fps make a big, bloody hole in anything it hits"
I have to agree.

Phil Shoemaker
Alaska Master Guide,
Alaska Hunter Ed Instructor
FAA Master pilot
www.grizzlyskinsofalaska.com

Anyone who claims the 30-06 is not effective has either not used one, or else is unwittingly commenting on their marksmanship.