seating bullet mistake

[dgeesaman]

Yes it takes more & more work to reform brass with ever bigger dimensional changes, but this does not change the spring back force gripping your bullets. The moment you stop adding all that energy, the neck just falls back into it's normal balance.

Test it for yourself:
Neck down 1thou (after spring back), seat a bullet, pull the bullet,, the neck springs back inward ~1/2thou.
Neck down 5thou (after spring back), seat a bullet, pull the bullet,, the neck springs back inward ~1/2thou.
Neck down 10thou (after spring back), seat a bullet, pull the bullet,, the neck springs back inward ~1/2thou.
So any way, the only attribute holding a bullet is the Force X Area of that ~1/2thou spring back.

If you think a bullet is held back (ballistically) by friction, you're wrong there too.
Test this for yourself:
Size necks all the same, take half to squeaky clean with a bronze brush, dry lube the other half with graphite or tungsten. Note while bullet seating that forces are way higher with clean necks (higher friction).
Shoot them across a chrono, and you'll see no difference in MV.
So bullets were neck released before overcoming frictional difference.

Now, if you want to see tension change, and MV change with it, simply adjust the LENGTH of a given neck sizing, to grip more or less seated bullet bearing. ---Sprinback Force X Area---

I agree but anneal in between those steps if you’re using the same piece of brass. Work hardening definitely changes the amount of spring back.

 

[mikecr]

It's just a test to get the jest of my point.
It's the grain breakage that causes the new balance, and why it's futile & detrimental to size down much beyond normal springback (excessively).

Think of brass forming like stretching a type of rubber band, whos grain structure breaks beyond ~1thou of stretch and will not allow recovery. So no matter what you stretch it to, no matter the forces it takes to do so, it only springs back ~1/2thou. It just yields to that new dimension.

With enough cycles of this, the rubber band will spring back less & less. It's structure is so broken that it resists movement in any direction. Without process annealing to recover the structure, the rubber band will crack & fail. It's not that it's springback force has changed, but that it's structure blocks that force from recovery. It's out of balance energy adding.
We need a useful range of this energy, so we NEVER desire a full anneal.

Ideally, we would neck size no more than 1thou (after springback), for no more than seated bullet bearing, and then perform a pre-seat expansion of necks with a mandrel at cal diameter (instead of using bullets to do this). Seated bullets would then be gripped by springback (as they are anyway) with minimal change to brass structure. With tension being force x area (PSI)(not friction, nor expansion forces), we would adjust tension amount through LENGTH of sizing.
If you keep your neck clearances reasonable along with this, necks can remain at consistent energy levels, providing consistent tension, for many cycles before annealing is needed at all.
This is good whether you anneal frequently or rarely.

No matter what you do though, be sure to load develop with your sizing plan in-place and stable.

 

[INTJ]

.....On another note...you trust your digital scale much? not meaning any dis respect but I still choose to use a beam scale due to lack of trust in digitals.

I take it you have not used a good quality digital scale. There are miles of difference between a Sartorius Entris or A&D FXI and a budget grade scale.

 

[6ShotsOr5?]

I usually prep cases up through priming and then set them aside until I know how many I want to charge. Usually I will have more prepped cases on hand than I’m going to charge. If I mess up on charging or seating a few, I just throw them in a bin and I will pull the bullet, recover the powder, and resize with no depriming pin later. Part of the reason is that I use a T7 turret press and my collet bullet puller is on a spare turret. I don’t want to mess with changing turrets just to pull one bullet.

 

[BondJamesBond]

I take it you have not used a good quality digital scale. There are miles of difference between a Sartorius Entris or A&D FXI and a budget grade scale.

Apology to OP for off topic subject... I've had a V3 in my cart for 3 months but trying to keep my ass at the rabbit hole lobby area.... but thanks for the nudge