Just me, but the 25/06 is a waste! Both in capacity, and accuracy. FOR A LONG RANGE VARMINT, I'll explain!
I went down this rabbit hole a few times. Fact is, today, many confuse long range Varmint, with long range Target! Two totally different subjects!
I built a 6mm Rem. AI a few years back and chose a 1-8 twist barrel,,, BIG MISTAKE! The reason I chose it, was the 6mm is overboar for the lighter bullets in this size cartridge. The 6BR is under bore for maximum capable velocity of the bigger 108's I wanted to use. My dilemma turned out to be the capability of the bullet to withstand the speeds I wanted to run it, and still get maximum accuracy!
It turned out I could run the 108's and 105's over 3400 fps. The problem was, the further I pushed the Bergers or the Hottenstiens beyond 3100 to 3150, the bigger the groups got! Accuracy was great out past 600 as far as I tested it, but by then the starting 3100 fps, left the bullets worthless for anything but making a little 6mm round hole, paper or varmint, in and out, no terminal performance. My issue with that was hell I could do the same thing with a 6BR and 20 grains less powder?
I will never again call a 1-8 twist barrel a varmint barrel. I also will never again consider a heavy for caliber bullet anything but what they were designed for, Long Range Target shooting. Just me, but I've always been a "if ya can't kick em----ya can't count em", kinda guy. I need a balance of speed, accuracy, and terminal bullet performance. Ya I want flat, and it's nice to cheat the wind, but we can do all that with todays balistic software and rangefinders, but without some bullet performance on impact, your simply not going to kick as many to count when you get out past 500 yards with a big heavy bullet!
Now back to the 25/06 in any configuration, I am building a 257 Bob AI for the simple reason, it will drive a medium to light bullet as fast as the 25/06 will. The 1/4 bore 06 might push a heavy bullet faster, but even that is marginal for the purpose of trajectory or more distance and still do some damage when it gets there. But trust me, a Nosler BT in 85 grains is pretty fragile out to over 700 yards, and yes, ground hogs have shown this in the past, more than once.
The next thing you will notice, is barrel life, and the rounds it will get before setting a barrel back. This is just a trade of we have to live with for either, 55 to 70 grains of powder will get less life than 30 to 35 in a 25 or 6 BR, but it will do the same thing a heavy bullet will do in the big cases.
I have shot the 22 Hotrod to the 25/06, and many in between. I have found the most efficient killing cartridge for ME, has been the 257 Roberts AI in the 1/4 bore for me. I also find the best combined accuracy, killing ability, and trajectory, combined, is with these middle wieght bullets, and the 1-10 twist is my choice to spin em. Plenty fast enough twist for up to 100 grains, and still run a 60 if thats yer thing. But the 60 is weak beyond 400 to 500 yards as a killer, and really gets weak in conditions in the varmint fields.
Again, this is just what I have found, and worked best for me,, and why I'm building mine this time with what has been my best results in the past 30 years! After trying the latest greatest, and most popular over that time. It just never worked for me!