Drop down to 6, 6.5, or 7 for starters....
Why? He already explained what he's doing and it requires a .257 and/or a .277 bore.
He want's to do something here rather than just follow the crowd.
External ballistics isn't following a crowd, nor is it an opinion...
But long range to some means working up a load distance to others....
6 or 6.5 would simply provide more options with fewer penalties is all.
But this is 'Merica....
This IS 'murica. You can pick and choose what you want. I mistakenly thought the OP wanted to prove a point that the .25-06 or .270 could do anything any other cartridge could do. I apologize for my tone here. Sometimes I get carried away. Hell, I'm old, LOL!
I agree with you 100% that you can do this a lot easier and cheaper with a 6mm, 6.5mm or even a 7mm because there's bullets and guns already on the shelf everywhere set up to do it. In those calibers it's a turn key deal. But that's not my goal to do what everybody else is doing.
I have wanted to build a long range .270 for about three years, just because I like to be different and not follow a crowd. It may not be the smartest move economically, but it scratches an itch. I still will go to hell swearing there's nothing magical about a 6.5 anything. If I wanted to follow the crowd I could go buy a Crudmoor of some flavor and shoot 600 yards with no problem (well with some practice).
But why would I do that? I won't shoot at game at 600+ and I'm not really a LR Paper Puncher (however I would be if I had a range big enough). If I build a LR .270 I will still limit shots at game to 300-400 yards. However, if I get the opportunity I'll wring it out on paper as far as I can see just to prove to everybody AND myself the .270 with the proper barrel twist and ammo can do it. It won't be a turn key or easy project but it will be a lot easier than it would have been 10 years back. And it will scratch an itch.
Anyway, that's my story and I'm stickin' to it.
