Neck sizing

[jamesharrison]

While I've never used one, apparently the RCBS X die prevents having to trim brass, due to shoulder / neck brass flow, and NOT, of course, due to grossly excessive headspace, caused by brass / chamber mismatch. If the die was machined to accept a bushing of the appropriate size, along with an appropriately [to your brass] sized mandrel, would that be the ultimate [as long as it is used, when required, in conjunction with a body or FL die to size the base]?

 

[liberty]

While I've never used one, apparently the RCBS X die prevents having to trim brass, due to shoulder / neck brass flow, and NOT, of course, due to grossly excessive headspace, caused by brass / chamber mismatch. If the die was machined to accept a bushing of the appropriate size, along with an appropriately [to your brass] sized mandrel, would that be the ultimate [as long as it is used, when required, in conjunction with a body or FL die to size

While I've never used one, apparently the RCBS X die prevents having to trim brass, due to shoulder / neck brass flow, and NOT, of course, due to grossly excessive headspace, caused by brass / chamber mismatch. If the die was machined to accept a bushing of the appropriate size, along with an appropriately [to your brass] sized mandrel, would that be the ultimate [as long as it is used, when required, in conjunction with a body or FL die to size the base]?

Just another option...

You can buy standard full length sizing dies from Forster, and they will hone the necks to whatever dimensions you want, usually in .001" increments.

Ends up sizing your brass like a bushing die but without a bushing.

I think they still offer this service.

 

[Meroh]

Only FL dies that use an expander ball work the brass twice.
It is also a fact that when using a neck sizing die - collet, bushing or expander style, the shoulder will have to be pushed back eventfully with either a body die or a FL die.
One cannot simply use a collet die and expect the same results every time because the brass will eventually jam in the chamber.
Cat

Yes, but if you are using it in the same chamber, it takes a while. Many guys do use a deprimer with a mandrel.

 

[Bad Bob]

I use a .222" mandrel in a Lee collet die, shoot max. loads in a .223 and never have to full length resize. Brass seems to last forever but eventually the necks split, all is good.

 

[iron cat]

Yes, but if you are using it in the same chamber, it takes a while. Many guys do use a deprimer with a mandrel.

I use a universal decapper for several reasons, especialy when I want to measure fired cases before sizing or when loading my Schuetzen cartridges.
Cat

 

[milsurpo]

I think the OPs original question was- why don't the resizing dies form the neck to the required size in the first pass rather than going past the desired size and then expanding it with the plug. I don't know the answer but, for 7.62x54, I have multiple expander plugs of different size that I use for rifles with different groove diameters which require different bullet sizes. That might partially explain why?

Regarding the wisdom of neck-sizing only, I totally agree with the guy in the video. Brass sized to fixed specs is part of the rifle design and neck sizing only doesn't allow the brass to do its job. By requiring "work" to stretch (elastically and plastically), properly sized brass actually reduces the "bolt thrust" substantially. By using neck-sized only brass you are increasing the bolt thrust. I don't want to do that with, for example, my Lee Enfields. Accuracy wise, with Lee Enfields I found a huge accuracy improvement (over commercial ammo) by simply reloading (with full-length resizing). In the rifles I tested, going the next step to neck-sizing only didn't really make a noticeable difference. With my most accurate PU Mosin I have found that, as the guy in the video suggests, running in just far enough to bump the shoulder back 0.002 or 0.003 inches yields by far the best results.

milsurpo

 

[senior70]

I think the OPs original question was- why don't the resizing dies form the neck to the required size in the first pass rather than going past the desired size and then expanding it with the plug. I don't know the answer but, for 7.62x54, I have multiple expander plugs of different size that I use for rifles with different groove diameters which require different bullet sizes. That might partially explain why?



milsurpo

I think it has to do with the expander on exit, makes the inside of the neck more concentric, whereas just squeezing it down may not leave a perfectly concentric surface for the bullet to seat on.