Brass flow into necks ?

[gunsandgunsmithing]

I didn't say necks don't thicken. I said to have ample clearance or skim them periodically and that the thickening is a result of the sizing operation

 

[AlNyhus]

FWIW, I had an interesting experience last season with necks thickening in my 30BR.
I had f-formed the Lapua 6BR cases to .30 with pistol powder and no bullet and then outside turned them. Over the course of firing them throughout the season, all the necks began to thicken a few tenths at a time. It wasn't from donut brass migrating forward....it was a thickening of the entire length of the neck in a gradual manner.
It's my belief that not using a bullet and the resulting quicker pressure drop didn't allow the neck material to be loaded against the chamber hard enough or long enough to 'set' the material. Subsequent firings after neck turning likely allowed the drift in thickness as the necks continued to be hammered against the chamber.
Good shootin' -Al

 

[SKWERLZ]

FWIW, I had an interesting experience last season with necks thickening in my 30BR.
I had f-formed the Lapua 6BR cases to .30 with pistol powder and no bullet and then outside turned them. Over the course of firing them throughout the season, all the necks began to thicken a few tenths at a time. It wasn't from donut brass migrating forward....it was a thickening of the entire length of the neck in a gradual manner.
It's my belief that not using a bullet and the resulting quicker pressure drop didn't allow the neck material to be loaded against the chamber hard enough or long enough to 'set' the material. Subsequent firings after neck turning likely allowed the drift in thickness as the necks continued to be hammered against the chamber.
Good shootin' -Al

Another BR guy mentioned that for fire forming there’s no real substitute for an actual bullets and appropriate charge.

Neary mentioned a similar issue, that’s why he fires them a few times first to fully form and stabilize the case before turning them.
Then you’re done.

 

[rsbhunter]

Now, I'm confused about "to set the material". Is this like a hardening of the brass? If so, wouldn't annealing nullify the "set"? Thanks for all the input, there's a lot of information here!!! rsbhunter

 

[SKWERLZ]

Now, I'm confused about "to set the material". Is this like a hardening of the brass? If so, wouldn't annealing nullify the "set"? Thanks for all the input, there's a lot of information here!!! rsbhunter

Is the setting just movement where it wants to go till it’s happy like a dog on the couch?

 

[mikecr]

Both Mitutoyos, 1 of them is useless imo.

Mine is good enough. I can sneak right into donut measure, no problem.
And take from a reloader who truly sizes minimally, it IS only sizing that leads to thickening necks.

 

[762plinker]

I wish you wouldn't have posted that. Lol....I have been preaching this for a year or better. So many big names argue too...why do you think Speedys pumpkin patch is in excess of probably 50 by now? Every Pumpkin that comes up for sale, he buys!

NOT TRUE..i buy them also...and for a very good reason

 

[6BRA]

Mine is good enough. I can sneak right into donut measure, no problem.
And take from a reloader who truly sizes minimally, it IS only sizing that leads to thickening necks.
View attachment 1442104

You would be in the minority by just neck sizing now days. But if it works...run with it.

 

[mikecr]

Could care less about mob mentalities. That's for sure!