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Yes, it will ensure consistency.
This is why neck-sizing brass makes life so much simpler...Especially with belted magnums, because it headspace off the belt, not the shoulder.
The simple fact is that cam over is NOT always desirable.
The easiest way to determine HOW MUCH sizing is required is to index your lock ring with 1/12 marks, each represent about .004" adjustment in height. Back the die out 1/2 turn from touching the shell holder and make a mark on the press and the die. Size a case, clean it, chamber it, if it is TIGHT to close the bolt, screw the die IN 1/12 as indicated by your lock ring indexes, repeat until a slight feel is felt on bolt turn down, then screw the die IN an additional 1/24 turn, this should give you around .002" shoulder bump.
I run a few Weatherby cases, I will tell you that this design resists sizing moreso than angled shoulders and can be a PITA to get right, sometimes you need to bump more than .002" to give reliable chambering.
Hope this helps.
Cheers.
Unfortnately the die, whether used as described above, or FL sizing back to minimum SAAMI specs, is still sizing the body smaller, even down to the belt. It is a myth that the die doesn't or can't size the entire body, as it is evident where the sizing stops at the expansion line. The belt itself is part of the solid head and cannot be sized anyway.
Thanks so much for the reply. I think I get it.... so basically the case gets fully resized even if you do not cam over...Unfortnately the die, whether used as described above, or FL sizing back to minimum SAAMI specs, is still sizing the body smaller, even down to the belt. It is a myth that the die doesn't or can't size the entire body, as it is evident where the sizing stops at the expansion line. The belt itself is part of the solid head and cannot be sized anyway.
This causes the head to shoulder dimension to grow, which we then need to bump back.
I have sectioned many belted cases, the expansion line gets closer to the belt on brass that is either thinner in the walls or thinner in the web. The worst culprit being Norma brass. It is often hard to distinguish where the expansion line is on Norma brass as the solid section of the case head ends right at the front of the belt, this can cause the bulge to happen if the chamber is loose in this area.
Whether you get the so called 'bulge' above the belt is partly due to your chamber design, brass brand you use AND sizing method.
I have not experienced the bulge in ANY of my belted magnums and I have/do run quite a few of them. To date, I have used 270 Weatherby, 264WM, 300 Weatherby, 340 Weatherby, 300WM, 338WM and 375 Weatherby. As well as 458WM and 458 Lott. Which are sized differently.
The only case I have trouble with is my custom 375 Weatherby, it has a very tight match grade chamber, I had to buy 3 different die sets and modify a shell holder by turning .010" off the top of it before I could get sized brass to chamber, as the chamber is .002" above minimum CIP spec, and most US dies are too long in head to shoulder length. Even with considerable cam over, the shoulder just wasn't being bumped back due to the cases lengthening during sizing. Feeler gauges under the case head worked, but it was fiddly and slow, hence the need to experiment with different dies. In the end the only set that worked were Redding.
If you think you are getting the bulge after a few firings, there is the belted mag collet die that can help, personally, I don't see any need for it, but each to their own.
Cheers.
