I have bought new Metallverken 8x57 brass to make 9.3x57 brass, the latter being quite expensive and scarce. The resized cases have a neck that is noticeably thicker at the base of the neck, where the old shoulder used to be, lekely as a result of the original brass being thicker in the shoulder area. Has anyone run into that isue with other barnds? Or, I might ask, are there brands of brass that will not present that issue?
Resizing 8x57 to 9.3x57: neck thickness issue
- Thread starter pacobillie
- Start date
Hornady 9.3x57 FL dies were used. Brass was sourced from Higginson powders.
It is a bit difficult to chamber, but I can close the bolt. It shoots well, with no signs of pressure. And no, it does not fireform.
what is the diameter of the neck when loaded with a bullet before being fired, and the diameter of the neck after being fired?
basically if you can slide a bullet down the neck of the case after firing with no resistance then you have enough clearance on the neck in the chamber that you are okay, if the bullet does not slide down freely then you may have to look into neck turning to get the clearance required in your chamber.
I don't have this issue when necking up certain brands of 30-06 to .375, but some brands require neck turning, if in doubt try chambering a piece of brass after necking it up, if there is no resistance chambering with no bullet, but then resistance after seating a bullet then you likely have to turn the neck to remove the newly formed doughnut
basically if you can slide a bullet down the neck of the case after firing with no resistance then you have enough clearance on the neck in the chamber that you are okay, if the bullet does not slide down freely then you may have to look into neck turning to get the clearance required in your chamber.
I don't have this issue when necking up certain brands of 30-06 to .375, but some brands require neck turning, if in doubt try chambering a piece of brass after necking it up, if there is no resistance chambering with no bullet, but then resistance after seating a bullet then you likely have to turn the neck to remove the newly formed doughnut
Diameter of the neck when loaded: .3875 near the mouth, and .3955 at the base of the neck, where the brass is thicker. Thus, the "donut" adds .008. BTW, once fired (reloaded) cases have a slightly less prominent donut, measuring .3935 (.002 less than unfired cases). Hence, it does fireform, but not completely.
Diameter of the neck after firing: TBD. I have no fired cases on hand at the moment. However, I tested before resizing and was able to insert a bullet through the mouth.
Neck turning appears to be the logical solution, but nobody makes a .366 mandrel for a neck turner, AFAIK.
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9.3 neck turning mandrel $16 at Brownells https://www.brownells.com/reloading...turning-mandrel-sku749002089-33872-65913.aspx
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Yes, but I would need to upload it to an image sharing site, which I cannot do at this moment.
I would look for a few pieces of 8x57 Winchester cases at the range, and try forming them, they might be thinner and not create donuts when formed.
Even if you keep using your Metallverken brass you will have donut problems as the brass keeps flowing into the neck. Meaning frequent neck turning to remove the donuts.
I had the same problem forming 7.65 Belgian Mauser cases until I tried using thinner Winchester 7x57 cases.
Even if you keep using your Metallverken brass you will have donut problems as the brass keeps flowing into the neck. Meaning frequent neck turning to remove the donuts.
I had the same problem forming 7.65 Belgian Mauser cases until I tried using thinner Winchester 7x57 cases.
Have you ever seen one that fits a Hornady neck turning tool?
only the ones that were made from a .375 mandrel.
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You should be ok then.
Update: I tried 3 other brands of brass. With new Norma brass, I get a similar ring at the base of the neck. With once fired RP (Remington) brass, i do not get a ring. Same with once fired surplus (nny) brass. Next, i am going to try fire forming the brass without a bullet, using both the Norma and Metallverken brass and measure the thickness of the neck wall of the fire formed brass, to see if it is brass or die related. For now, it seems to be brass related.
May be worth calling Hornady about the mandrel, they'll build it for you, sounds like you'll need it one way or the other. No doubt they will charge you a small arm for it, then again too, maybe not, but, if you need it, just do it. That is also why I liked the 21st Century neck tool, they'll build inside reaming and any shoulder angle cutter for theirs, along with the neck expanding mandrels, and trim cutters, for whatever you need.
