375 H&H Mag Encore reloading

[pcpharm]

Firearm: Encore 375 H&H mag
Situation: purchase of barrel, Lee full-length & neck only dies along with both fired and unfired cases.
Story: I purchased a 375 H&H Mag Encore barrel with full-length and neck resizing dies, and both fired and unfired cases. All cases were fired from the barrel purchased. However, that barrel is now on my receiver, not the receiver from which the cases were fired.
Question: I know you are only supposed to neck resize cases when they will be fired from the same firearm. The problem is that I have the barrel that all the cases were fired from, but the receiver was not on the barrel when the cases were fired. I want to resize all the necks for the cases as many are “out of round”. However, I am uncertain whether I need to full-length resize or only neck resize. So is it the just the barrel that dictates whether to neck resize or full-length resize, or is it both the barrel and the receiver? If just the barrel then I should be able to neck resize the cases and should be ready to reload. But if both the barrel and the receiver make up the chamber then I should full-length resize.
I am currently leaning to full-length resize just to be on the safe side. Thanks for all your comments and advice in advance.
PCP

 

[R.W.Dale]

With reguards to your premise of only neck sizing. This is incorrect when loading for anything but a bolt action DOUBLY so for a break action single shot.

Go ahead and sell your neck size die. With an encore you'll never use it.

Basically what you go for loading for a break action is you need the case head to clear the breachface by .002" less than what the standing breachgap measures. Because of the way these actions work this WILL require pushing the shoulder back to some degree w each firing.

Just neck sizing and as a result letting the case head drag the breach and wedge forward on closing is a surefire recipe for vertical stringing, inconsistent lockup and ignition.

Mike Bellum has some great articles on this

 

[RhinoDefense]

Adjust your die to size up to the belt. Only FL size when the belt needs some correction. I've used my brass for 10 firings before it wore out. These are full strength .375 H&H loads.

 

[pcpharm]

neck resize and headspace

Thanks for the discussion so far. I have read Mike Bellm's presentations and I have kept copies of the articles on my own Word files. I take those into consideration when I reload for the Encore. I constantly think about the fact that the rear of the breech is the weakest point in an Encore and the case lengthening may eliminate the headspace.

However, not all neck resizing dies are the same. The forester dies provide the option of "bumping" the shoulders while the neck resizing. I have a forester die for my Encore in 30-06 and I have used it to reload for that caliber. When neck resizing I always check the headspace for 0.002 inches to make sure I do not need to full-length resize the cases. Yet I also recognize the difference between the shoulders on the 30-06 and the 375 H&H.

If you only resize down to the belt, what parameters do you use when to decide that the case needs to be full-length resized? Do you use headspace again? Nice thing about the break-open actions is that headspace is not that hard to measure, as long as you can do 3 things at once.
PCP