Even though this is about making cartridges, it goes hand-in-hand with the "Steyr Project" thread at this site, so I decided to post it here in Firearms & Optics.
Attached you will find a photo of the four cartridges based on the .376 Steyr case for which I am building rifles. They are from left to right:
1) The parent cartridge - The .376 Steyr.
2) The .358 Steyr,
3) The .338 Steyr, and
4) The .323 Steyr. (I won't call this the 8mm Steyr, because that label is already confused.)
A couple of days ago, I received from Hornady a Custom Grade Bushing Type Neck Sizing die. This die has interchangable bushings that allow custom sizing of the neck of the particular case in question. In my case, I had the chambering reamers made for each of the cartidges so that they had exactly the same headspace. Therefore, using this die, I only have to change the bushing to resize any of the four cases. That's the good news.
The bad news is that Hornady does not make any bushings above .30 caliber unless special ordered, and none above .338 regardless. The good news is, I now have machinery to make my own bushings, and have. Tonight I made the .358 and 8mm bushings only, as I have the means to resize the .376 and .338 case necks without
having to use the Hornady die. Still, I will make bushings for the .376 and .338 shortly. Won't be long before I actually have these rifles in hand.

I'm still practicing my thread cutting, and when I"m satisfied that I can do it to my own standards, I'll start chambering barrels.
The first out of the chute will be the .358 Steyr. The second the .376. The third and fourth will both be .323s. One chambered to shoot the 195-grain Hornady International, and one to shoot the Sierra 125 Spitzer. I don't have a spare .338 barrel in hand at the moment, and I still have my .338 MAI to blood, so the .338 Steyr will bring up the rear. I am seriously considering a .411 Steyr. I bought some 300-grain .405 Win bullets (.411" in diameter

) and looking at them I am impressed. I think they would fit the .376 Steyr case well. That rifle might get made before the .338 too.
Paul