I have a 277 fury with a 16" barrel, the Sig 150 grain accubond box ammo shoots about 1" at 100 yards and averages 2995 fps. This is the higher pressure stuff of their 2 offerings, I believe it's supposed to be 80k psi but some guys on the internet seem to "know" differently. Pretty impressed to see the least, Sigs 150 grain accubond box ammo for the 270 with a 24" barrel advertises 2800. To shoot 200 fps faster than their 270 box ammo with the same bullet and much longer cartridge and barrel, that's pretty simple.... its faster. I don't know about the 7 backcountry, but he also asked about the 277 fury, and I can testify to it. I have been shooting, resizing and now simply reliading it for a couple years. I personally like it quite a bit. Going to be pretty awesome with a 6.5 fury too. I'm not sure why Federal would start with a long action though, seems like they should have started with a 80k mag to REALLY set it apart, or stick with a short action like Sig and continue to branch from there. There are other cartridges that can utilize a long action to get the speeds they r getting with the 7 backcountry. It's a start to a good thing, just like Sig though... lots of calibers are going to increase about 2-300 fps here in the next few years I'm guessing. lol
