sizing new brass
- Thread starter thefiremeister
- Start date
Neck size - always. No way to control neck tension otherwise. The bullet basically becomes an expander mandrel.
I want to say that brand new Lapua brass in the 308 flavor will give you nominally like .008 neck tension! A bit tight there...
I want to say that brand new Lapua brass in the 308 flavor will give you nominally like .008 neck tension! A bit tight there...
I know what you mean. At least you shouldn't have to FL them or do any primer pocket cleaning. FL sizing is what sucks worse than anything in my opinion.
They do come way tighter than I'd typically like (and some random due to the dented case mouths during shipping). I run an expander ball through them, then transition them over to my Redding Competition bushing sizer die to end up at .002 - .003.
They do come way tighter than I'd typically like (and some random due to the dented case mouths during shipping). I run an expander ball through them, then transition them over to my Redding Competition bushing sizer die to end up at .002 - .003.
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i have just loaded some of the lapua brass... but the last 260 brass I got from them was bad.. had to neck size them...
necks all beat up.. out of round.. guess the ups guy decided to see how much he could throw them around are something..???
Unfortunate but yes, rough handling and/or poor packaging (can you say Midway, lol) really sucks. An expander mandrel will solve this kind of a problem much better than neck sizing alone. You want the "problems" pushed to the OUTSIDE of the case neck, not the inside.....
When you guys say you "run them over an expander mandrel" is that like going 2/3 into a FL Die?
I am imagining enough stroke that the case mouth goes up into the die and through the expander ball/button, but not all the way up into the die? Why not just use a neck die then? Or is it completely different than that?
I am imagining enough stroke that the case mouth goes up into the die and through the expander ball/button, but not all the way up into the die? Why not just use a neck die then? Or is it completely different than that?
Yeah, I've heard of that happening with the expander balls. I do have many mandrels as well that I use interchangeably (only on new brass - after that they are good to go with neck-sizing only). I actually take an approach above and beyond what most people would I think... I actually polish and impregnate the expander balls with Tungsten Disulfide in a small rock tumbler with aluminum BB's. I do it to neck-bushings as well. It only applies a .05 micron thick film that makes the surface ridiculously slick. It lasts for quite some time as well. Molybdenum Disulfide powder can be used as well. Ultimately I am relying on the bushing to do the sizing. The expander ball/mandrel is just to enlarge a tad.
I would imagine that if anyone wanted to do this also you could probably just do it in your vibratory tumbler perhaps. It's just another step to make that much less friction in the process overall.
Check out: https://www.ws2coating.com/blog/a-co...num-disulfide/
Sort of. In your situation I would not buy more tools if you dont want to and just run them into the FL die as far down as I could without bumping the shoulders back any further as they are likely at the minimum side of saami spec. (provided the new brass chambers. If it doesnt you might have a super tight chamber and would need to bump them but thats for a <1% of the time situation) If you only go to the expander ball youll get your consistent neck tensions but you will possibly induce some runout/concentricity issues.
The expanding die is like the expander ball part of the die but a mandrel; a solid metal bar to round everything out and force the brass inconsistencies to the outside away from what grips the bullet.
http://www.accurateshooter.com/techn...-neck-tension/
https://www.youtube.com/watch?v=PA2U8WHHr9U
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I didn't know they make the sizing mandrels. I had always thought there had to be a better way than to pull the sizing button out of the brass on the upstroke. I think I'll try a mandrel and see if that makes a difference for me.
i always resize new brass, more for the consistent neck tension more than anything.
