7-08 twist thoughts

[spclark]

I picked a 1:9 for somekinda 7mm before I took a ‘road less traveled’ with a wildcat 7 built on 308WIN case. Pushed 180 Hybrids to 2,800 fps, accurate enough to tie an NRA LR (1,000 yd) Nat Record in ‘16, 200-15x.

7-08 won’t push 180’s that fast but 160-165’s ought to do OK in a 1:9; I’d go with 1:8 were I contemplating your build.

“Fast(er) twist will stabilize heavy(er) bullets better at low(er) velocities” is the general rule that applies here.

For my 2nd chambering in that wildcat I chose a 1:8.5 for that reason. Only fire-formed a new batch of cases innit so time will tell if for me that rule’s holding up.

 

[std7mag]

I have a 280
AI that shoots a long heavy barnes bullet in one hole groups but they all go through target sideways.
And I think that is a 9 twist.
I think I would go with a 8 twist

If your trying to shoot a 160gr monolithic bullet, your essentially shooting a simular length cup & core 180gr bullet.
Monos are longer in length than equivilant lead core bullets.
But even at that, it shouldn't be keyholing with a 280AI.