7mm RM Head / Case separation

[bigedp51]

All good info, thanks to everyone! So, Rick357, I measure the shoulder length using the Hornady comparator bushing (0.420 in.), from the head. However, I've been bumping since day 1 so I guess I should've waited until the bolt gets harder to close.

I'll try your method, it seems very logical to me!

I'll post the results later!

You can partially full length resize a case and make it longer than your chamber. Meaning you do not need to fire and neck size a case several times trying to get the shoulder to move all the way forward.

1. Fire form the case by jamming the bullet into the rifling, this will prevent the case from stretch on the first firing.

2. Then place a .010 to .020 feeler gauge between the die and shell holder. This should make the shoulder move forward and the case will be longer than the chamber. You then start using thinner feeler gauges until the case will chamber without excessive bolt closing effort or drag on the base of the case.

NOTE, Redding makes competition shell holders that do the same thing as using a feeler gauge. There are five shell holders in a set in .002 increments that will push the case from .002 to .010 "LESS" into the sizing die.

Below shows the exaggerated effects of full length resizing, and you case see the case shoulder is forced forward at the blue dotted line. And the object of full length resizing is to push the shoulder .001 to .002 below the red dotted line. And the closer you push the shoulder back to the green dotted line the more chance you will have of stretching and thinning when the cartridge is fired.

 

[Chefboubou]

Thanks Bigedp51. For now, my goal is to extend the life of my cases, even if neck sizing may not provide the best accuracy. That being said, I think I'll make a test with a few of these new Nosler cases. I'll neck size part of it, and I'll FL size a small portion of the cases each time. I'll be able to compare the impact of both techniques on the case life.

 

[Hitzy]

I've been bumping since day 1 and clearly, either I over bump, or bumping is simply not what my rifle likes.... I bought a set of 3 redding dies so I'll start using the neck die... case life can't really be worst than what it is right now....

That being said, I have a box of new Nosler cases. I weighted these cases and they are light weight (214 gn) compared to the Rem (231 gn) or Hornady cases (229 gn). I'm afraid these thin cases won't last very long. At least I told my wife I'm reloading to save money! [Chuckles]

If your Nosler are coming in at that weight, they are Norma made brass cases, and quite high quality. Nothing to worry about there.