260 or 6.5x55??

[Mikecr]

Again, 22" is irrational for the 6.5x55.
It's difficult to describe why that is, but I'll try.

Accuracy is the ultimate power, and same accuracy at higher velocity nodes equals more power.
It was mentioned that so & so get ~2800-2850fps with 140s & short 6.5x55s.
Anyone can get this accuracy and velocity node from 6.5x47L, which uses way less powder.
The 6.5x47L would also be using faster powder for same optimum load density, it can run higher chamber pressures viably, and releasing bullets cleaner with lower muzzle pressures.
Given sufficient competence in load development and shooting -applied to both scenarios -I would bet on the 6.5x47L stomping the crap out of 6.5x55(with irrationally short barrels), especially at distances beyond 500yds
Now put a 28" barrel on the 6.5x55, and I would not bet on either until 1kyd. By then, the edge is definitely in the 6.5x55's favor.

So to summarize, you can remove the advantage of many cartridges when you choose a barrel that's too short. Doing so merely raises the advantage of smaller cartridges over your choice. And ~2850fps with a 6.5x55 is not impressive, regardless of 100yd grouping.

 

[codyadams]

Again, 22" is irrational for the 6.5x55.
It's difficult to describe why that is, but I'll try.

Accuracy is the ultimate power, and same accuracy at higher velocity nodes equals more power.
It was mentioned that so & so get ~2800-2850fps with 140s & short 6.5x55s.
Anyone can get this accuracy and velocity node from 6.5x47L, which uses way less powder.
The 6.5x47L would also be using faster powder for same optimum load density, it can run higher chamber pressures viably, and releasing bullets cleaner with lower muzzle pressures.
Given sufficient competence in load development and shooting -applied to both scenarios -I would bet on the 6.5x47L stomping the crap out of 6.5x55(with irrationally short barrels), especially at distances beyond 500yds
Now put a 28" barrel on the 6.5x55, and I would not bet on either until 1kyd. By then, the edge is definitely in the 6.5x55's favor.

So to summarize, you can remove the advantage of many cartridges when you choose a barrel that's too short. Doing so merely raises the advantage of smaller cartridges over your choice. And ~2850fps with a 6.5x55 is not impressive, regardless of 100yd grouping.

As I said, my 260 AI is getting 3000 fps, and that's using 47.8 grains of powder, but with a 30" tube. My dad's 6.5x55 is getting 2855 with the same weight bullet using 51 grains, but a 24" barrel. Also, the 6.5x47L will easily go in a short action, while the same is not true with the 6.5x55. I think either would be a good cartridge. Just depends on what the op is looking for

 

[Mikecr]

The 260AI, 6.5x55, and 6.5x47L are great cartridges.

Nothing about the straight 260 is great, and it hasn't and will never take off in popularity.
In lighter bullets it's beaten across the board by the 6.5x47L.
In heavier bullets it's badly beaten by the 260AI/6.5x55 (which are basically the same).

In short barrel design, the 6.5x47L (123-130gr bullets) stands out as best of the three.
I just think OP should be informed of this while he's choosing.