Re: Belted Cartridges?
What you're getting into here, about the bullet taking up 1/3 of the case, is a run-in between what the cartridges were marketed to do, and what they're being used for in certain circles. The idea for these rounds was to produce a cartridge that delivered magnum performance in an envelope of a short action. Trade-offs had to be made somewhere, and that's part of the deal. for someone using these outside the box, such as a competitive shooter, this opens up a lot of other possibilities. That's where things get interesting. Again, if you're building a rifle for a specific purpose, you're the one who gets to decide what is, or is not a worthwhile trade-off. The F class shooters are gravitating heavily towards the SAUM and/or the WSM's in 7mm. Since the issue of having them work through a mag in a short action isn't a concern for them, like I said, things get interesting. Personally, I do like the idea of getting away form the belts once and for all. They add nothing, and are a potential trouble spot. The newer designs eliminate these potential problems and allow us to concentrate on other things.
Your comments about the 300s are spot on, and exactly what I was getting at here. The 6mm PPC is the most accurate cartridge ever developed, but you don't see it used for 1000 competition. The trade off to a somewhat less accurate cartridge that has the power and BC to hang in at the extended ranges make that the only logical way to go.