Full Length resizing and preventing case head separation.

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chuck nelson

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Apparently this is a problem that I was not aware of and there appears to be several myths around it and neck sizing only. I’m putting this in the hunting rifle forum as I feel it is most applicable here. I’ve added three videos advocating FL resizing that include the why’s from credible sources to illustrate the point. I have included my own simple tutorial below that.

https://youtu.be/ECUcIeak7CM

https://youtu.be/lLG2kSrD40g

Start this one at 11:00 minutes.

https://youtu.be/ZrTKhVPPi34



Here is how to do it with simple tools, a factory chamber, and an I care more than zip attitude.

Here is 308 brass fired in some unknown chamber that I’m going to resize for my sons Kimber Montana 7-08.

SoDNamT.jpg


A standard FL die. Screw die down until it touches the shell holder and back off one full turn.

EesA8hG.jpg


Remove your firing pin assembly so you feel no resistance when closing the bolt. I have smoked the brass for demonstration purposes. This works on a rifle with a fixed blade ejector and will not with one that has a plunger type. Resistance and feel works for both. If the firing pin assembly has been removed.

wfqvU4L.jpg


Move die down until the resistance when chambering the round just goes away. This shows about two thousandths bump. Notice the slight ring.

jVVeGC2.jpg


Or do the above process with this $40 tool. This one is from Sinclair.

euOH60p.jpg


This expander ball gives between three a four thousandths neck tension which is plenty, but will do.

ynXVZaQ.jpg


You can fire these Winchester cases, unsponsored, in a factory chamber, using standard dies 50 times and they will not separate. AND you do not have all the baggage associated with neck sizing only.
 
Are you confident that the 2 thou bump on the shoulder is enough for the brass to be easily chambered in all factory chambers?
Or just this chamber?
 
2 to 4 thou bump is what I do and that depends on a few things including preference.

2 thousands bump is just that. It would be the same regardless of what chamber it is in. You have to be measuring cases fired in that chamber to know.
 
I was speaking wrt the example you were showing above. Not previously fired cases in the same rifle.
Would the full length sized brass you made for your sons rifle fit in others?
 
It might, it might not. Why does that matter?

You do know that the ring on the neck in the second picture is caused by his chamber don’t you.

The reason I’m illustrating what I am is because that is what I was working on this morning. I know what 2 thousandths clearance looks like in his chamber. You can apply the same method when you resize your fired brass in the chamber it was fired in.
 
Is there a difference between “full length sizing” and “neck sizing plus shoulder bumping” tapered cases?
With the method above I’m not sure your fully sizing the case to the base. (?)
 
Excellent article!

Have you tried machinist's (Prussian) blue?

Flame anywhere near my reloading bench is verboten.
 
scout_289 said:
Flame anywhere near my reloading bench is verboten.
Click to expand...

Really not a worry with smokeless powders... just keep the candle at one end of the bench if you are really worried. A lit cigarette would be more dangerous as it could fall into an open can of powder.
 
Get a set of Redding Competition shell-holders and forget everything you ever heard about screwing dies in and out, measuring to the shoulder, smoking cases and gauges. The only gauge that matters is the rifle chamber and you already have that. Use the .010" over one until the cases start to get tight. When they get tight go down .002" at a time until they aren't tight anymore. Write it down when you find it and use it forever for those cases and all that follow. Press flex becomes a non-issue. Sizing for multiple rifles of the same caliber with the same die becomes kid's play.

Done, done and done.
 
chuck nelson said:
They are not an option with a Forster press. Whidden makes 10 thou click die lock rings that look like the cats PJ’s.
Click to expand...


You couldn't be more wrong. I have a Forster co-ax and use the competition shell holders for 7mm rem mag, you just need the standard shell holder adaptor plate which can be purchased direct from Forster.

https://www.forsterproducts.com/product/shell-holder-adapter-plate-for-co-ax-press/

Also a click die lock ring will not remove the slack in the press, albeit there is very little in the co-ax, it is still present.
 
nevanevan said:
You couldn't be more wrong. I have a Forster co-ax and use the competition shell holders for 7mm rem mag, you just need the standard shell holder adaptor plate which can be purchased direct from Forster.

https://www.forsterproducts.com/product/shell-holder-adapter-plate-for-co-ax-press/

Also a click die lock ring will not remove the slack in the press, albeit there is very little in the co-ax, it is still present.
Click to expand...

Yes, I am well aware of the adapter. I prefer the “float” of the their shell holder. It’s part of the reason I bought the thing.
 
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