Do you have to resize brass if you never fire and pull the bullet?

[C-130 Dude]

Your last neck sizing is bullet seating. Every time.
This normalizes tension to mere spring back force per area applied.

You could size a neck down 10thou under cal, and another 1thou under cal, seat bullets, pull bullets, and both necks will spring back to the same ~1/2thou under cal. The force behind that spring back is what grips .xxx area of bullet bearing.
This force varies with brass hardness, which is a condition that does not have to be refreshed.
The harder the brass, the stronger the spring back force.

As far as bullet pull force, this is barely related to tension, and mostly friction.
Replacing a bullet may upset prior friction, but this makes no difference to internal ballistics (your chrono).

If you were only loading your cases once, I'd agree with you. But to be able to reuse cases after firing as much as possible, you'd have to anneal them prior to resizing. You could decide not to anneal, but you would start from an unknown starting point. Idea being to reduce work hardening which is detrimental to case longevity.

 

[spladi]

Question for you guys, when doing load development and finding pressure, say you work up 6 increasing powder charges and find pressure on the 4th charge. How do you treat the last 2 unfired cases? I know I can pull the bullet and just dump the powder back in my keg, but do I need to resize the brass before using again? I'm pretty sure the answer is yes but I haven't run across this yet in reloading as I just started.

Appreciate it fellas.

I'd say it depends on the brass's spring back and for what the intended purpose might be..........probably good for fouling shots and therefore save the primers and bullets from possible damage too..........assuming a bolt gun is used.

 

[liber]

I'd say it depends on the brass's spring back and for what the intended purpose might be..........probably good for fouling shots and therefore save the primers and bullets from possible damage too..........assuming a bolt gun is used.

Shouldn't matter if it's a bolt gun or a semi-auto, it's the chamber that matters, not the bolt.

@C-130 Dude yes, I check the length, that's the whole reason for checking in a gauge after sizing. If the case either doesn't fit or extends past cartridge length, to the trimmer it goes. I always try to make sure the case is within spec as they will go out during a fire, depending on the chamber. I have had too many loose fitting cartridges if I don't resize, as the die brings the neck down so it has proper tension. That's more critical in a semi-auto where the seating will change as the action cycles. All of our mileage can and do vary. I do all of my reloading on a single stage press these days, no progressives.

 

[Mikecr]

If you were only loading your cases once, I'd agree with you. But to be able to reuse cases after firing as much as possible, you'd have to anneal them prior to resizing. You could decide not to anneal, but you would start from an unknown starting point. Idea being to reduce work hardening which is detrimental to case longevity.

This is a reason to choose rational clearances and minimum sizing.
So that you don't have to anneal frequently -or ever.
It's all in our choices