Sizing Basic Unprimmed Brass: Straight wall to Bottle Neck

T

theshootist

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I have been unable to find (what I would call) regular unprimmed brass in 375 Ruger. So I ended up buying some Hornady basic unprimmed brass sight unseen. Imagine my surprise when I open the box to find straight wall cases without any head stamps.

A quick search on the internet did not find any info specific to my dilemma. How do I form these straight walled cases into bottleneck cartridges?
Will I need to anneal? These puppies are expensive and I hope to not have to learn the hard way (the usual route).

Any info would be greatly appreciated.

Thank you
 
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I suspect that it would be best to neck down and set the shoulder in stages. The case mouths are probably annealed as received. Might have to repeat later?
 
tiriaq said:
I suspect that it would be best to neck down and set the shoulder in stages. The case mouths are probably annealed as received. Might have to repeat later?
Click to expand...

Is necking down in stages be done by just lowering a full length sizing die in stages? I'm wondering if the expanding mandrel should be removed until the final sizing?

Regarding annealing, the case mouth is the same color as the remainder of the cartridge. (color is uniform throughout the entire case)
 
Sizing necks - to make some 9.3x57 brass - from 8x57 - there is likely a minor headspace issue on my older rifle - so, as per Internet, I wanted to create "straight wall" brass to start - I chose to go from 8x57 neck, used the elliptical sizer ball in Hornady dies to take that to 9.3 mm, then a sizer ball from a 41 Magnum die to get more or less "straight wall". From there, I worked back down in one stage to reform to 9.3 x 57 - I just ran them into the 9.3 FL die - had to work the die down in small steps at a time, to get the shoulder where I was just so able to close bolt - that put the 9.3x57 shoulder further ahead than the 8x57 shoulder was. I read that others do similar to create formed "new" 303 British without causing case stretch inside at the case head - to get the case to "headspace" on its shoulder, not on its rim. I did not have to anneal any of the new PPU cases that I used to transform from 8x57, to slightly longer 9.3x57, but I intend to do so, after I fire them once.

Not real certain how far that you have to close up your necks from the Hornady Basic to 375 Ruger - might end up wanting to use an intermediate size in between?? Likely some handgun diameter, I suspect? It was my choice to ignore the rim and belts and attempt to headspace on the shoulder of the cases - you may chose to approach that differently?
 
Same colour is because of tumbling.

Necking down in stages refers to reducing the diameter in steps. If I were making .243 out of .308, I would perhaps use a 7mm-08 die, then .260, and then .243, rather than trying to go from .308 to .243 in one pass.
 
tiriaq's suggestion about "steps" has a lot of merit - some years ago, though, not having intermediate sizes, I ran IVI 7.62 brass directly into a 243 FL die - and made about 50 x 243 Win cases - in one step. Was with a single stage RBCS press - I used a snipe on the handle to force the case in - and bent that handle. Would have been much easier with a compound leverage press and intermediate size dies - is how I would do that task today.

For whatever reason, my Remington 788 in 243 Win accepted those cases without neck turning - I did trim all to uniform length, chamfered and seated 85 grain Speer .243" bullets - I might still have a couple dozen of those brass left here.
 
So I opened a ticket directly with Hornady just to see if they would even respond, they did and quite promptly in fact.

The Hornady technician replied,

"As long as you deburr the outside of the case mouth it should lead right into the neck sizing area of the 375 Ruger sizing die. Otherwise you may be able to step this in with something larger and a neck, like a 416 Ruger die. Otherwise our custom shop can build you a step forming style die. I will tell you also there are alot of customers out there looking for this brass and you may be able to sell it and buy standard 375 Ruger cases. Thanks"

I still figure I'd be hard pressed not to have a case buckle in a 375 Ruger full length sizer... anyone have any experience or advice with this?
 
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