Setting up a Full Length die.

Here's a question but first let me set it up. As discussed when you set your die so that it has started resizing the case body, it starts pushing the shoulder forward. On once fired cases the shoulder is typically a few thousandths away from contacting the chamber shoulder.

Question

In your experience, when sizing once fired brass, is it possible to push the case shoulder far enough forward to contact the chamber shoulder?

Last time I checked, I was only able to push the shoulder .001" or so on once fired cases and that was not enough to enable the body die to contact the shoulder and place it exactly where I wanted it. Is there any other way to accelerate the brass expansion sequence so that you can size for a slight crush fit on once fired cases?

I've had dies that would not touch the shoulder of once fired brass, this will happen with smallr/tighter chambers.

Sometimes the shoulder does not move forward as you start to resize the case. In my WSM (the example I documented), the case did not grow at all during the resizeing, I think this is due to the chamber being pretty tight compared to the die, so the amount of body resizing that took place was minimal.

To get the growth forward you are asking about, I only know of 2 methods.
1) high pressure loads.
2) Use a load that allows bullet to land contact for the first firing. This is no different than fireforming for wildcats. This method, along with high pressure is probably your best bet.

AJ
 
AJ , I was doing it the way you described . I bought a set of the redding comp. shell holders . they are in .002 increments . they just seem a lot simpler to me . I've read that the die will be more square to the shell holder if you bottom it out against the shell holder . whats your opinion on them ? this should be the same thing only a different way of achieving it . thanks Jim

http://www.redding-reloading.com/pages/compshellhldrs.html
 
AJ , I was doing it the way you described . I bought a set of the redding comp. shell holders . they are in .002 increments . they just seem a lot simpler to me . I've read that the die will be more square to the shell holder if you bottom it out against the shell holder . whats your opinion on them ? this should be the same thing only a different way of achieving it . thanks Jim

http://www.redding-reloading.com/pages/compshellhldrs.html


I use them, in fact I used one of the shell holders in the pics, since I left my standard shellholder at Dogdingers house. On my 7mm Mag, I can adjust the die to just touch the +.010" shellholder and then reload with the +.002" shellholder and get a perfect bump. I like them and have them for the mag boltface as well as the .308 boltface.

AJ
 
Woods,

Yes, but I think it depends on the chamber and die.

I started loading for my dad's (old but mint) 308 on the weekend.

The way I set up the gauge this makes sense to me, but simply look at the difference.

Once fired brass was X.X28" as I sized I went as high as X.X32" at one point. For that combination therefore 4thou "increase" in case head to datum line distance at a certain setting.

The die does seem to be sizing the base and body a lot before even touching the shoulder and sizing effort is quite a bit, even on my Rockchucker with Imperial wax. Far more than my 300WM in a Redding body die.

The brass is an once fired (old) local brand that seems quite thick (I'll measure necks at some point) and I suspect something like WW may size easier, but I've never got into brass thickness and sizing effort, so I've no idea if this would have any effect.

The dies are mid 1980's RCBS.

Ideally I like to neck size only and then set up the die to bump the shoulder only after 3 or 4 firings of neck sizing only. I've got no way of sizing the 308 necks only at this time, so I've set it up right away. I think that the 3 -4 firings way is a better way to allow for minimum resize. I generally find that even with full loads shoulders are only formed really nice and crisp after minimum 2 and preferably 3 firings (I suppose that takes us back to the discussion on springback! :rolleyes: hmm...). Anyway, that tells me that I still have some slop after a single firing. Once I feel that slop is taken up I adjust the die (under normal circumstances).

Not that I have a wealth of experience, but just how I do it....

I've used the bullet in the lands as AJ described to take up excess headspace on a first firing. The other way is to create a false shoulder (never tried it). As I understand it you expand the neck one caliber up and then partial size it back down to create a jam fit. You can do this with new brass.
 
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Shims or Redding comp shellholders

Oh... and I currently still use the Redding competition shellholder (I think it's called). This allows for contact between the die base and the shellholder and you can "customise headsapce" adjustment whilst still making die/shellholder contact. You could also put a washer shim over the case between the shellholder and the die.

Whether this is desireable is probably another question.

I suspect that takes care of creating a "dead length" sizing set up which in theory may be more repatable. For me it was an easy way to set up the die. Certainly easier than screwing it down in little bits. Is it money well spent? Well.... not sure, but it's also easy for me, within limits, to change the headspace now by swapping the shellholder and leaving the die untouched if I want to check something out.
 
I did a search on headspacing so I can try to understand it. I am fairly new to reloading. I bought an RCBS Precision Mic for my 22-250. I had a hard time understanding the directions until I started reading this topic. My fire formed once fired shells were showing .002 over factory new. I just kept sizing them until I got it to .001. I am assuming that is correct for me? Also, at first I kept using the same shell until I got the correct# and then did the rest of them (checking every 3rd one to be sure they came out the same). Were you using the same shell or did you use a different one everytime you needed to seat a little further? Thanks for the info.
 
I did a search on headspacing so I can try to understand it. I am fairly new to reloading. I bought an RCBS Precision Mic for my 22-250. I had a hard time understanding the directions until I started reading this topic. My fire formed once fired shells were showing .002 over factory new. I just kept sizing them until I got it to .001. I am assuming that is correct for me? Also, at first I kept using the same shell until I got the correct# and then did the rest of them (checking every 3rd one to be sure they came out the same). Were you using the same shell or did you use a different one everytime you needed to seat a little further? Thanks for the info.



I use the same one . after you shoot your brass 3 or 4 times you will probably need to change your die setting a little , or use a different redding shell holder . your brass will loose it's spring back . ( or you will anneal the brass at this point ) with you measuring once fired brass you probably don't have your true chamber size yet , do to your brass spring back . so you could be over sizing the brass . on once fired brass I can use the .010 redding shell holder . after 2 or 3 firings I need to use the redding .008 shell holder . so I'm actually sizing my brass .002 more to be able to chamber it easy . Jim
 
Being that I have the FL die set up for my rifle now, can I get brass to resize correctly for my rifle if it has been shot out of another rifle?
 
Being that I have the FL die set up for my rifle now, can I get brass to resize correctly for my rifle if it has been shot out of another rifle?



with you using a F L die , I think you will be able to do this . only do a couple and try them , before you load a bunch that don't fit . or the other gun could be chambered a little shorter than the first gun . in this case you will not be bumping the shoulder when you resize it , the first time . Jim
 
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