Regarding barrel length and sd, I have had better sd numbers with 24" and 26" barrels on rifles i have had vs 16 and 20" rifles with handloads. I assumed it was due to the burn being more complete in the longer barrels. But perhaps if i had done ladder testing for the shorter barrels, my results would have been different.
I appreciate your rifle suggestions, they are certainly good ones. For me, if i am going to have a 26" bolt gun, i would probably go for 300 norma or 300 win mag. In fact, i think my next rifle will be a 300 norma on a mausingfield action.
I was set to build a 6.5 cm on a mega maten 14" railed reciever set. I liked the switch barrel ability of the predatobr, because i can carry a second barrel in 308 instead of an entire upper. I am hoping to get decent accuracy out of it, if i dont, i will sell it.
Flatline bullets, mabey it was more optomism than i should have had, but after reading the snipershide review were frank mentions that "this bullet like the 160gn 30 cal flatline will work in a semi auto. I think the 2900fps load is about perfect to run in a gasser. This will push this rifle to the next level especially if you want to compete with it." I understand he is talking about a 6.5cm and not a 260, and I wish larue would have made this in a 6.5cm instead of a 260, but am hopfull this will still work. I did contact warner tool, and they said tht their bullets are not jump sensitive like some companys vlds, but we will see.
I really appreciate all of the info provided here especially from defender3! This will be very helpful for narrowing down bullet and ammo choices.
One last thing i have been considering on the 22 vs 18 inch barrel length is stiffness. An article i read by Dan Lilija
http://riflebarrels.com/a-look-at-the-rigidity-of-benchrest-barrels/ leads me to believe there is a significant difference between a 22 and 18 inch barrel, although he is looking at much heavier profile barrels.