Open up those necks with a bigger mandrel if you're collapsing the shoulder by just seating bullets. That's way too much seating pressure for sure. Or get the right bushings that don't size down the neck as much when you're taking the 7mm necks to 6mm.
I’ve got the bushing that’s .003 smaller than loaded neck size and then I’m using the Sinclair carbide mandrel. I’ve always had good luck with this combo, but there is a good bit of seating force. Have you had good luck with any other mandrels? I’ve used some other brands before but since they aren’t carbide they end up gauling necks and end up being a pain.
Brushing the inside of the necks with an oversized nylon brush on a drill bit helps significantly with seating pressures.
I’ll give that a try, thanks. It’s a .242” mandrel
Definitely brush the necks. And I would moly them also. But I bet just brushing them solves it. Virgin necks on brass can be super sticky, until you get them once fired and put a layer of carbon inside there.
BTO is 3.19, thats all I have on my Phone. I will post my notes when I get to the shop.
I put it on the bullet, so no powder issues. Very little to none of the wax can touch the powder. I haven't observed any problems. I have used moly as well, the wax works better for this application.
It would be really hard to quantify barrel life vs. a few grains less powder. To get your brass completely fireformed will typically take 3 fireings or so. I like FF loads to be around 90% of max. New ADG brass fired in my 30 Nosler doesn't need the shoulder moved back, until after the 3rd time. Things are much more consistent after the first time however.
Cool, thanks for the info. I’ll just keep rolling with 65 grains then and bump up after the first firing.
I was wondering this same thing. If it was better to have a softer shoulder or harder shoulder to prevent buckling. I’ll run them through my amp and see if it’s better.
I've only necked down from 30 to 7mm, 7mm to 257, 6.5 to 6mm, and 6mm to 22. Always did it in 2 steps with a bushing die, or with a Hornady universal neck die.
Load data? I'm getting similar groups, maybe a bit better. 67gr V570 with 115 dtacs. I only have 30ish rounds fired so far. 18" Ace barrel around 3050fps. Faint ejector marks. Peterson brass.
Peterson brass, 115 dtacs, 65gr n570, 20” ace sp3 barrel, 3.155” COAL, 3106 average velocity over those 85 shots. No increase in velocity from first to last shot so far.
You're fire forming with 67gr N570? Isnt that near max load in formed brass? Id be forming with 59-60gr H1000.
I didn't knowfire forming made that big of a difference. Maybe I'll try that with the rest of my brass.
I don’t recall how accurate the FF loads were, but they were better than yours. I would remember those.
