Re: 338 edge?
I had a .300WM Remington Sendero that I turned into a 338Edge. I had Shawn Carlock do the work for me and he did an excellent job. The 338 Edge if loaded to capacity will usually get an average of 150 fps faster than the Lapua. There's a guy in our club that shoots our 1 mile shoots with us, who was using a Lapua and rechambered to a Lapua Ackley Improved, just so he could get the velocity that we are getting with our 338 Edge's. (There are about 8 of us that are shooting Edge's at our "1 mile shoots" in our club, one who shoots the 338 Lapua Ack Imp., a couple who shoot .50BMG's, and a .408 Cheytac)
As stated before, if you anneal your cases, you'll get longer life out of them. Nosler is also making brass for 300 RUM, which is a little better than the Remington brass. For me, I haven't had much issue with the Remington brass and have gotten multiple firing out of it. I shoot Lapua brass for .308 and know that it is great brass, but for the 338, I just don't feel like I'm missing anything by not shooting the Lapua.
I've shot my 338 Edge to 2200 yards and have bested 338 Lapuas, 408 Cheytacs, and .50 BMGs. I've knocked over steel silhoutte targets at over 600 yards with the 338 Edge and destroyed some MGM targets with it at 500 yards and under. It's a very powerfull round!
Shawn Carlock has actually come out with a 338 Edge +P, which is sending a 300 grain Berger bullet at over 3100 fps. Only downside is it is a single shot. But, truthfully, when I'm shooting 1500 yards or more, I'm usually single loading anyway.
There is no fire forming the cases either. Just run the brass through the sizing die, prime, and load, then go shoot.
I see no downsides to the 338 Edge at all. Some have said that you can't buy ammo "off the shelf" and that's why they go with the Lapua. I'd rather load my own than pay $100 for 20 rounds of Lapua any day, and just make sure I always have a surplus.
I don't think you will be disappointed with the 338 Edge at all.