Having never owned a magnum (yet). One of the things I recall reading on another site is that because of the belt, the cartridge tends to stretch a bit more. And as a result you cannot reload a belted cartridge as many times as you can a non belted cartridge. Is this true?
What is the purpose of having the belt on the cartridge? Does it make the cartridge stronger under the heavier powder charges?
The belt is their to alow a place to set your head space from on the case , I personaly can't see where the belt would make the case any stronger in a properly chambered gun as I've seen a couple guns that would make a doughnut just above the belt.
As for the cases not lasting as long that maybe true if you FL resize them evertime , if they are neck sized only or beter yet resized with a collet type die they will last for a good while , I'm on my 5 reloading on some 300Winmmag brass from Lapua , I fireformed and trimmed to length after the fist time and I'm still a few firings away from having to trim
I think that the original purpose of the belt was for strength 50 or more years ago. Kind of like high brass shotgun shells.
I think that most hunters kind of "expect" a magnum to have a belt. A good example of the "cosmetic belt" is the little 240 Wby I shoot and even more so the old 224Wby. Can you imagine a Wby cartridge without a belt? That would be funny.
The belt is on there solely for headspace... or rather thats what it was intended for. Thinning in front of the belt will happen... but it depends on how much differance there is between your brass and the chamber on the first firing. Personally, im a big fan of false shoulder fireforming belted cases, and using this method, they will lasy just about forever... or untill the primer pockets open or the neck splits, whichever comes first.
Necking the case up one caliber, then back down to the origional caliber with a FL sizing die that is adjusted up out of the press, moving the neck-shoulder junction forward some amount. This amount should be about .010" longer than this dimension in the chamber. This causes the cartridge to headspace at this point instead of allowing the case to be slammed forward as far as the belt, then streached back as pressure builds.
This is exactly how all of the ackley "improved" cartridges work... and if theres more than .020" differance case to chamber... its the ony way to go. Though honestly... im beginning to think its the only way to go regaurdless.
Stuff required to neck your caliber up is yourFL die, and about $15 of other stuff, and its very simple.
Belted cartridge cases can last as long as non-belted cases, if loaded properly. I have been reloading .300 WM for about four years now. When I first started, I full-length resized and my brass lasted about 3 or 4 times before incipient case-head separation. After backing off the resizsing die a bit to do partial resizing and headspace on the shoulder instead of the belt, I have reloaded many cases 12-14 times without any problems.