Almost no neck tension on new brass?

[Basic user]

Ran into something odd a few days ago with some new Alpha 6.5cm brass. Grabbed some virgin cases to start loading for a new gun, and wasn't happy with the .262 expander ball in my Forster sizing die; I could feel not a whole lot of resistance (there was some, but not what I was wanting) when seating the bullets in my inline die/arbor press combination. (I'm using the K&M press that has a short arm).
So I took the expander stem out of the die, chucked it up in my drill and polished on it a little to get it to .260 for a little more neck tension. Seated a few more rounds and NOTHING. ZERO difference in seating feel. How??
I was soo shocked I sized a case with NO expander ball in it, and seated a bullet in it after doing that and there was same neck tension, which is very little. I am so confused I have no idea what is going on. Could this be because the cases are brand new? Could it be bad brass? I'm guessing a lot of springback? Why dont my already loaded rounds from 2 weeks ago have this? When I try to pull a bullet out of my previously loaded cases it's really hard, and now all of a sudden they pull out really easy. I measured the od of these new bullets and they're the same as the old ones I loaded a while ago. Why I'm so confused is because this is a new anomaly for me. I've been loading rounds like this for a year now, and when I move to progressively smaller expander balls the amount of force needed to seat the bullets goes up. And now, all of a sudden out of nowhere, nothing I do changes the super light neck tension I have now. Nothing I do changes the super easy seating force I now have when seating... I have four Forster dies in 6.5 creedmoor and theyre all the same.
Have any of you experienced this?

 

[skatz11]

It sounds your sizing die is roughy the same neck OD as your new brass. That’s all I can think of to cause what you’re seeing. You didn’t mention a bushing size so I’m assuming this just a regular sizing die.

The die has to reduce the neck diameter down in order for you set the ID you want with the expander.

 

[Basic user]

I'm thinking the dies squeeze these necks down to .260 minimum (checked with neck gage pins) Now all of a sudden 4 thousandths neck tension feels like one lol. It's like these necks have a ton of springback and flex right back to the original od, or like the bullets are now all of a sudden slipperier than before.

 

[AllenOne1]

Sounds like you are running a bushing die with no bushing in it.

Measure the neck OD of the new brass, size it, measure neck OD, mandrel the brass, measure neck OD, seat a bullet, measure neck OD. Report those measurements back.

 

[FLIGHT762]

I have a Mighty Armory 308 Win. die that will not size the necks enough of any brass that you would need a .333" or less bushing. I have a bunch of old Winchester brass that needs a .331" bushing and some Hornady brass that needs a.333" bushing. That M/A die will not size the necks enough to get proper neck tension.

My Federal brass, newer Hornady brass, and a few other brands that need a .335" or larger bushing will work fine in that M/A die.

That same die wouldn't bump the case shoulders down to SAAMI minimum (1.630"). I had to send it back and had Wayne shave off .008" off the bottom of the die. It bumps fine now.

I don't know if the O/P got some thinner brass that his dies won't neck down enough. Might be worth doing some precise neck measuring and maybe talking to Alpha.

 

[spife7980]

As with every thread where people have issues: write down and share real measurements of the diameters fired vs sized vs seated. You’ll find your answer.

 

[918v]

Which Forster die do you have? The standard FL die should have a .284” neck. That should give you plenty of neck tension.