Seating Cast bullets

Potashminer

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So, not sure if this is "Reloading" or "Cast Bullet" question - will try here first.

I am working with a 9.3x57 rifle. I am using new 8x57 PPU brass - neck sizes up nicely with a 9.3x57 Hornady sizing die with the elliptical sizing button and a tiny dab of grease. Turns out to be nice close fit in the rifle chamber neck when a .368" gas check bullet is seated.

To seat that bullet, I used a Lee Universal Expander - just bumped the case mouth to create a "flare" - seems to seat fine - I do have a Lyman "M" die on the way to improve on that. My issue is that I can definitely feel that "flare" as I try to chamber the cartridge - that "flare" is being flattened back as the cartridge goes into the neck. Not seeing a Lee Factory Crimp Die listed for 9.3x57. 9.3x62, 9.3x64 and 9.3x74R - yes, but not 9.3x57.

So, looking for suggestions or ideas how to "flatten" back that flare on the case mouth, or, eventually, that "cup" from the "M" die, once the bullet is seated. The cast bullet does not have a crimping groove, so a roll crimp is not going to work, I don't think? I can not be the first person to have to run into this - looking for ways to deal with it!!
 
I thought of that for the flare - just a "kiss" on the roll crimp shoulder to bend that flair back to straight. Doubt that will work for the "pocket" from the M die, though - sounds like that is about 1/16" - .0625" deep? Do not have the "M" die yet, but more likely to create a "ring" just back from the case mouth??
 
I have an M die for 375 H&H on the way - Lee no longer lists an M die for 9.3 (.366"). So I will turn / grind it to fit. From Internet (Cast Boolits? Gun Boards?) had read to size the neck portion .002" less than sized cast bullet and to size the "cup" part at .002" to .004" larger than cast bullet size. So, about .004" difference, if I can actually do that. And, you are correct, it may turn out to be no matter. Still curious to hear what others who load cast bullets into 9.3x57 have done?
 
The "M" die is a Lyman item, unfortunately it is sized for jacketed bullets in most instances. I've loaded cast in 7mm Mauser, 308, 38-55 and pistol calibers - I can't see the 9.3x57 being much different.

In most instances a LEE powder through expanding die will do the trick. It is "M" like in design. Unfortunately LEE does not sell a 9.3x57 die set.

Before I can make any specific suggestions, I'd have to know a few more details.

What size are your bullets?
Have you fireformed your brass with a mid to full power load with jacketed bullets?

When I loaded for 38-55 my issue was that most die sets are designed for .375" bullets. To shoot well, my rifle, like most 38-55's worked better with a .379" bullet. I was using LEE dies so I bought a expander for a .379" bullet.

NOE makes and sells these for LEE dies; https://noebulletmolds.com/site/product-category/expanders/expander-plug-rifle/page/3

Most seating dies will close up the flare, if you don't flare too much. I have a LEE universal flare die, it is not a finesse tool, I use mine very little, just for one off or experiments.

My first choice would not have been PRVI brass, especially for necking up. I see Tradeex is sold out of Norma brass, that's too bad.

If you're not going to fireform with jacketed, you may have to get a bit fancier with your case forming. When I shoot cast in my 35 Remington the shoulder gets pushed back. I expand the necks to 416 and then neck the cases back down.

If you were to do something similar, it may work better. You've necked all your cases from 8 > 9.3mm, but before going to 416, an anneal of the necks is probably in order. If you are using new PRVE brass, you may be able to get away without annealing. Then size in your FL die just enough so that your bolt closed with some (but not much) force. A bit of flare should get you going from there.

I admire your wanting to keep your gun in it's original chambering, admirable. Most shooters have the chamber reamed for 9.3x62. Also kudos on using cast. I've also used cast in a 416 Rem Mag, recoil is more in the 30-06 > 300 Win Mag class.

You should be able to achieve your goal, it's just your starting form the wrong direction. Dies are designed to size down, all the dimensions are such that the cases come out a bit friendlier if you were reforming and necking down. Hence my comment of fireforming before shooting cast. But, IMHO the PRVI brass will be your biggest nemesis. PRVI brass is about 20 gr lighter than my R-P brass. It's not that it's bad, it's just that it's not as good. Like the old "Good" "Better" Best" rating. Your best choice would be 9.3x57 Norma or Lapua brass.
 
I have used the sizing die to lightly remove the flare. Doesn't take much, and did the trick for me.
*edit Should mention I did this with a straight wall case, not bottle neck.
 
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Thank you for comments, nitro-express. Regarding brass - I see that TradeEx is Out of Stock for Norma brass - do not know if I could have swallowed that price though!!

I decided to experiment with 10 cases - new PPU 8x57. Sizing and forming - from various web sights, I picked up on the "over expand" and then size down. I did start with the increase from 8x57 with the 9.3 Hornady expander. Then I turned a .398" insert to go into the Lee Universal expander body, with a taper, ran the cases over that, and basically created "sort of" straight cases. Then started working those cases back down in the 9.3 die, so that they chambered with a bit of a drag as the bolt handle closed - basically right back to pretty much snug, but not camming over, with shell holder touching die bottom. Oddly, those 9.3 case chamber (with a bit of drag) - the parent 8x57 do not - bolt stops hard before closing.

I then bumped one of the cases with the taper from the Lee Universal Case Expander - the cast bullets that I have are gas checked and sized to .368", and was able to seat that one. It also did chamber but I felt a "stop", then "release", as the bolt was being pushed forward the first time - did not feel that the second time - does not appear to be any amount of that flare left, so I am assuming it got "flattened out" on that first trip into the chamber neck. Hence, considering something like a FCD to "flatten out" the case mouth
 
I am not familiar with the M dies mentioned here but I "flare every rifle case (30-30, 32-20, 3855, 38-56, 35 Rem, and of course 100's of 45-70) I seat a cast slug into, and so far have only found one set of dies that wont roll crimp while seating or more often I run them thru again after seating with the seating plug turned out a bit and the die body in a bit more. The Redding Die set for the 35 Rem will not crimp at all but does seem to re-form the case neck to a straight entity.

With some of the cast shooting & testing I have done, I think case mouth tension is one of the most important things to consider. You are using GC based slugs so that will somewhat temper the effects of case mouth tension that effect plain base slugs. Hard cast with a BN of 25 or so will also be mostly unaffected by case mouth tension. Slug with a BN hardness of 15 or less will definitely be affected by a tight case mouth. When being seated, the case mouth, if tight, will downsize the slug just as if you were pushing it through a sizing die and can cause leading. I am lucky in that I have a lathe in my shop and I cut custom case mouth sizers plugs for every slug type I use. I endeavor to have not more than .002" grip on the slugs and count on the crimp to hold them in place in the tube magazines. Even with the Pc'd slugs I pretty much use exclusively, I still cut a plug that is exactly .002 larger than the coated & sized slug.

I do have a Lee universal flaring die, I used to use is quite a bit when I was just purchasing hard cast commercial slug but since I cast softer & PC all my slugs , it sits unused now.
 
Thank you for comments, nitro-express. Regarding brass - I see that TradeEx is Out of Stock for Norma brass - do not know if I could have swallowed that price though!!

I decided to experiment with 10 cases - new PPU 8x57. Sizing and forming - from various web sights, I picked up on the "over expand" and then size down. I did start with the increase from 8x57 with the 9.3 Hornady expander. Then I turned a .398" insert to go into the Lee Universal expander body, with a taper, ran the cases over that, and basically created "sort of" straight cases. Then started working those cases back down in the 9.3 die, so that they chambered with a bit of a drag as the bolt handle closed - basically right back to pretty much snug, but not camming over, with shell holder touching die bottom. Oddly, those 9.3 case chamber (with a bit of drag) - the parent 8x57 do not - bolt stops hard before closing.

I then bumped one of the cases with the taper from the Lee Universal Case Expander - the cast bullets that I have are gas checked and sized to .368", and was able to seat that one. It also did chamber but I felt a "stop", then "release", as the bolt was being pushed forward the first time - did not feel that the second time - does not appear to be any amount of that flare left, so I am assuming it got "flattened out" on that first trip into the chamber neck. Hence, considering something like a FCD to "flatten out" the case mouth

You are on your way, that's just about how I get-r-done. I use a modified 416 decapping pin in a universal decapping die (all LEE). You set-up does the same.

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I try not to overflare. I measure the case mouth before flaring and try for no more than about a 0.010" increase, ballpark. I then fine tune up or down depending on how the bullet seating goes.

A bit of fiddling, but you may want to try removing the decapping rod out on the FL sizing die and run the ammo in just far enough to put a bit of "crimp" on the case mouth. I've never had an issue, usually the seating die has enough of a closing effect when set to crimp.

I had a bit of a flare issue with a pistol caliber lately, I ended up adjusting the seating die a bit to help, and then the crimping die did the rest. Without the "bump" from the seating die, the case was a bit hard to start into the crimp die. Without the bit bigger flare, seating bullets was an issue. Not the same as yours, as my set has separate seating and crimping dies, but it illustrates that ofttimes a bit of fine tuning is needed. Not all dies are created equal, in my example the Dillon dies I use have a few features not found in other brands. My seating die has a bit of a taper inside to remove some of the bell, I just had to fool with the die and seating stem to find the sweet spot.

Nitro
 
Potash miner. I know that a case needs to be flared when loading a lead bullet but the base of your bullet is armour coated when you seat the gas check. Try seating a couple of your bullets into a non flared but well inside chamfered case. I suspect that you would see if any lead is scraped off the bullet above the gas check.

With regard to the unavailability of the Lee factory crimp die in 9.3x57 I wonder if a 8x57 crimp die with a 9.3 insert would do the trick? You need to call Lee to see if this is possible.
 
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There is another thread going about seating bullets into 9.3x57. Finally got most parts today - going to try to shorten the inner part of a 9.3x62 Lee FCD to work on the shorter 9.3x57. Just have to figure out by "how much" - 9.3x57 case lengths are perhaps from before such a thing was "standardized" - CIP and Norma do not agree - what I created from 8x57 brass is shorter then the shortest listed by either, but that is what I have to work with, so thinking I will modify that FCD to work with what I have... Can get "red neck" as all get out with spacers and shimming washers to gain some length, but have to actually cut it to make it shorter!!!
 
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