RE: Will 4 inches on a barrel make much difference?
velocity will be somewhat lower (want to say 10-20fps per inch of barrel out to..24 or 26")
accuracy...less rifling..i guess it could, but i really dont know..
whats your intended purpose/shooting style??
when i was shopping for a long range rig, i found right away i liked a LONG heavy barrel..why? that extra weight helps stabilize and steady things...atleast for me it does. that 26" full heavy barrel is long and heavy...leaving the gun way front heavy(so bad i have to sling it upside down because it wont stay upright!) but when on the bipod or laying prone, im much more steady with it than any of my other rifles...
but i bought the rifle with 1 thing in mind...long range groundhogs from a sitting location not far from the truck...didnt buy it to walk..didnt buy it to stalk..didnt buy it to hunt the woods...i bought it for sitting ontop of the highest hill with the best view of the most groundhog holes and making it happen from that spot..usually sitting not far from the truck...i have carried it and done walking with it...its doable..but gets old..lol..made alot of standing, freehand shots with it too..