I just got a New Savage 308 rifle for my long range target work and I'm using factory Hornady Match 168Gr BTHP ammo. It shoots great for factory stuff but when I got out to the farther ranges, 4-500 yards I could not hit crap with it. I'm using a Leupold Mark 4 LRT 6.5-20 scope and I'm dialing for my ranges. My question is how much difference does barrel length make on the speed of the bullet exiting the muzzle? Hornady shows a velocity of 2700 FPS for this round but my gun has a 26 inch barrel and I was wondering if it is faster or slower exiting the barrel if it would throw off my range dialing for those longer distance shots? I don't own a chronograph so I was wondering if there is a basic way to calculate this or if the speed difference would be very small that it would not matter that much for dialing in at those ranges. Any help would be appreciated. BTW here is a pic of my new rig..