so it's 2 completely different approaches to sizing brass. I have been on this forum for months now, reading all I can and I see this a lot. some do...... while other don't, but most posters don't tell us the WHY. would both posters like to tell us the why this time, please that is. I'm just trying to get a better understanding.
Bill Hodkinson
Here's a previous Q & A session that might help.
F/L Sizing is best!
Q: I am looking at a neck sizing die but would I be giving up anything by not going with a bushing die? Also what are the advantages of neck sizing besides not overworking the brass.
A: By not going to a bushing die you give up the option of fine tuning your load.
When you only neck size brass, you DO overwork it!
It's NOT a matter of frequency, It's a matter of the distance brass has to be worked/pushed back to its original dimension and the additional force required to do that, that defines Overworking.
When you full length size, regardless of chamber size, you're pushing the shoulder down about .001", pushing it inward about .0005" and pushing in the base/head area about .001", and squeezing down the neck a requisite distance, each time you pull the handle on the press. To do all of that, you need only one die.
When you neck size only, the body of your case is not touched and continues to expand a small amount each time it's fired, until such time, that you can no longer chamber it. To bring it back into the original designed dimension now requires an additional die [more money for the die manufacturers, now you own TWO], and a greater force to get it back to the designers specs [hence more force, over a greater distance = overworking]
By Full Length Sizing each and every time you reload will ensure: 1. The brass is worked very little, 2. You'll always be able to chamber your perfectly dimensioned round, and 3. You'll only need one die [preferably a bushing die].
Q. So a Harrell's would be what you mean right?
A. There are many fine custom die makers.
However, for $75 shipped, from Harrell's:
http://harrellsprec.com/index.php?crn=207 , you not only get all the proper sizing dimensions built into the die, you also get a bushing cavity with the right amount of play to ensure that only about 70% of the neck is sized. The remaining 30%, that's not sized, ensures the neck [and the entire cartridge] is centered in the chamber. Again, all for a modest price!