Re: I think 284win is the real deal.
So long as we're shooting the shit about 284s...
I had a hard-on the size of texas to build one. I built mine on an FN SPR action, and I'm magazine limited to 2.965" or so COAL, but I load the 175smk to 2.950". It shoots well, and goes about 2835fps or so.
Anyway, my partner finally rebarreled his rifle from 308 to 260. I TRIED to convince him to put together a 7mm of some flavor, but he didn't want to. He just wanted to do something solid and proven.
Anyway, we had the chance to do some 400-1500 shooting in some 5-10mph non steady wind a could weeks ago at TVP and it was fun to see how the two cartridges compared, running them side by side. He's running the hornady 140bthp @ ~2850fps from a 26" Bartlein.
Unfortunately, my "killer" 284 setup wasn't really *that* much better. Honestly, he hung right there with me to about 1000 yards. I was needing a tenth or two less wind at 1000, but it wasn't anything crazy. My 284 is about 1/2mrad flatter than his 260 to 1000.
At 1200 yards, I was able to score hits on a 12"x12" plate a bit more consistently than he was, but it wasn't drastic. Neither of us were consistent past 1300 yards, but I was the only one of the two of us to connect past 1300.
The key difference I was seeing between our chamberings, was my splash. When I missed, we saw it. Period. When he missed at ranges past ~900 or so, we had to watch carefully, and even missed a few. Past maybe 1100ish, we missed a LOT of his splashes...meanwhile, even my misses at 1500 were all seen easily.
This all got me to thinking. Mind you, I really like the 284 chambering, because it gets solid, respectable velocity out of the high BC 7mm bullets, without being "overbore" and suffering from particularly poor barrel life like the magnum 7s. However, for typical "tactical match" useage (our main game), the 260 is (gulp) perhaps a better choice. Less recoil, less blast, easier to shoot fast, and totally adequate for tactical useage out to 1000 yards (and we know the 1000 yard tactical shot is a rarity). Plus, it is a lot easier to get/use 10 round magazines with the 260, and again, it's a proven, solid performer. There is a reason it has become so popular.
Don't misunderstand, I LOVE 7s, and I don't regret mine, just sharing some thoughts/experiences.