Load Development with new brass?

[gaza916]

Thoughts?

If the goal is to be as accurate and repeatable as as I can be with my own reloading skills, surely starting with new brass (Lapua) will mean that my headspace is likely longer than the 2 thou I would bump it back to for my chamber? Or is headspace, say 2-10 thou, irrelevant for accuracy? I would have thought variance of that magnitude would have an effect on pressure and henceforth accuracy/comparable results?
I will be body and neck sizing prior to firing.

Standing by for constructive and informed comments!!!

 

[NullMac]

Perhaps depends what the use is?

If you are stalking, forget about it. Accuracy is a chain and there are other errors that will dwarf any error from this. If you find a good node and load in the middle then any effect from this will be mitigated anyway.

If its benchrest, dunno, good question.

 

[mealiejimmy]

Some people run new brass through a full length sizing die to bump the shoulder back to same as their existing brass.

Cheers

Bruce

 

[Jelen]

For stalking purposes, with new Lapua brass, just run it through the necksizer die. This will expand the neck evening out any dents. Then just load in increments to find a safe node.
There is no need to worry about head space for the first firing, or even the second firing.
After that you can set up the body die as per instructions to give you 2thou bump if you wish.
.

 

[gaza916]

Some people run new brass through a full length sizing die to bump the shoulder back to same as their existing brass.

Cheers

Bruce

But you can’t bump the shoulder back if it’s already shorter than your chamber?

 

[mealiejimmy]

You're right - my apologies.
In that case just shoot it and treat it as fired brass

Cheers

Bruce

 

[jb1]

By all means start with new brass, Lapua being a good choice. After the 1st firing your brass will all be the same as before(Externally), you can then resize to the chamber, i think there is more magnitude going on in your head than the brass or in the accuracy. What the change in brass will do is likely alter the case capacity, thats going to affect pressure more than the 0.001 -0.005 in case length depending on previous brass.