Case Separation?
- Thread starter slinkylegs
- Start date
Here is how to set up a sizing die without any fancy measuring tools. Screw sizing die in and stop just before it touches the shell holder, set it so you can see day light between the die and shell holder. Take a fire formed case and smoke the neck and shoulder with a candle, match, lighter, whatever until it is black. Run case into the die and take a look, the "black" will tell you how much you have sized the case. Screw the die in very little at a time and keep experimenting until you see the tell tale mark on the shoulder, set the die so the mark on the shoulder is very light. This is the delicate part, play with the die setting and chambering the case, what you are trying to do is size the case just enough to chamber. Now you have a case with minimal shoulder set back and you will have acceptable head space. No more separated cases.
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BattleRife
CGN Ultra frequent flyer
- Location
- of No Fixed Address
The only sizing gauge a guy needs is your rifle. Size the case, and see if it drops easily into and out of the chamber under its own weight. If not, screw the die in a little further, and try again.
slinkylegs
Regular
- Location
- Hudson Bay, SK
So I took some micron cloth and was able to get the line off, as seen in the picture:
Now, the distinct black line is gone, but there is still a noticeable change in the brass where the line was. Is that due to oversizing the brass? It would make sense, because most of the brass I have for the 204 has a similar look at the same location. Accuracy has been good.
Also, I will try to incorporate the tricks suggested by BattleRife and Bad Bob when I get to reload next (been too busy as of late).
I don't see anything that would make me think you're over-sizing your brass. That is just the line where the die sizes to - dies don't typically size the very bottom of the case.
I think a lot of people replying haven't read the whole thread and are just assuming case separation is whats happening based on the title, for which the usual cause is oversizing the brass... But if its not a case separation issue (which it doesn't look to be) then I don't think there is any evidence to suggest you are in fact oversizing the brass. (This is not to be confused with me saying you're NOT oversizing them. I don't know. What I'm suggesting is we don't have enough evidence to determine if you are or are not oversizing at this point in time.)
I think a lot of people replying haven't read the whole thread and are just assuming case separation is whats happening based on the title, for which the usual cause is oversizing the brass... But if its not a case separation issue (which it doesn't look to be) then I don't think there is any evidence to suggest you are in fact oversizing the brass. (This is not to be confused with me saying you're NOT oversizing them. I don't know. What I'm suggesting is we don't have enough evidence to determine if you are or are not oversizing at this point in time.)
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- Location
- Western Manitoba
Some time ago, I was playing to make brass cases to fit something they were not originally - I had to oversize the necks, then size back down to create "false shoulder" - at that time I ran into a write-up about using the rifle chamber to set the die - so, start too far out, the brass will not chamber - when the sizing die is set just right, the bolt closes - and you can be as fussy about that as you want - bolt is snug to close versus bolt is "sloppy" to close - that might depend on what you want to use the thing for - and that might result in daylight to your shell holder or not - and tiny little adjustments to the sizing die - one full turn of the 1-12 threaded die body is like .0833" - you are going to adjust way smaller than that - .001" or .002" at a time. But, rather than rely on "made in China" tools and gizmos, just use your rifle chamber to set your sizing die.
slinkylegs
Regular
- Location
- Hudson Bay, SK
Should a person take out the firing pin for this process then? I imagine that needs to happen, otherwise the bolt closes fairly snugly
slinkylegs
Regular
- Location
- Hudson Bay, SK
If anything, I would have been resizing back to factory/book spec, or at least that would have been my intention. I did trim them back once a couple loads ago.
As an aside, is there a universal decapping die that works for the 204? All I have seen are for 22 or larger cases.
If the line cleans off, it's not a crack!
Just the mark your dies make. Proceed with die adjustment as suggested. Removing your firing pin is indeed the best way for precision as there is no interference involved from the spring. Not everyone removes the firing pin all the time though, myself included. Sort of depends on the rifle and it's purpose.
- Location
- Western Manitoba
I did not remove the firing pin. I was making 9.3x57 brass from 8x57 brass. My belief is that my 9.3x57 chamber is longer than "normal" but I do not own headspace gauges for 9.3x57 - so I do not really know. However, I do know that the brass that I made, with that die, fit into that rifle's chamber, very nicely.
270WSMXBolt
Regular
- Location
- Delta B.C.
You may need to clean your dies if you were able to wipe the line off, or clean the cases before resizing. Cheers
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To repeat and add to the good advise from Suther...Because head separation can be very serious...
To positively check your brass for excessive stretch in the head area get your self a piece of wire...Give one end a short 90 degree bend that still fits the down the case neck and feel your way down the inside of the case wall...If you are getting close to head separation you will feel a ring indent in the case wall at the head area of the case...It is quite obvious to feel...If you feel that divot ring the case is unsafe.
When you have to trim your necks the brass has to come from some where and that somewhere is more than not from the head area of your case.
With hot loads and over sizing one might be shocked at how few reloads and the head area of the case becomes dangerously thin.
To positively check your brass for excessive stretch in the head area get your self a piece of wire...Give one end a short 90 degree bend that still fits the down the case neck and feel your way down the inside of the case wall...If you are getting close to head separation you will feel a ring indent in the case wall at the head area of the case...It is quite obvious to feel...If you feel that divot ring the case is unsafe.
When you have to trim your necks the brass has to come from some where and that somewhere is more than not from the head area of your case.
With hot loads and over sizing one might be shocked at how few reloads and the head area of the case becomes dangerously thin.
slinkylegs
Regular
- Location
- Hudson Bay, SK
Yes, I have done as you, Lastgun, and others have suggested. I first used a dental/automotive pick, and then the wire from a twist tie. My wife also did it, and neither could feel a definitive crack in the case. I've concluded that it must be a die mark, and that it isn't an imminent case separation issue. However, I will do my best to size my brass more carefully, and I may end up buying newer stuff, as this Winchester brass is likely nearing the end of its life anyway. The primer pockets are starting to stretch a bit, at least of many of them
I found some very disturbing rings on some of my cases years ago - turns out it was from my cases rubbing against the sides of the plastic cases I was using!!
Cat
Today I sized some S&B 303 Brit cases I bought used. I found two that had what looked like separations about 1/2 the way around. I do not know what they were fired it, but they looked good, (not banana'd) and did not take a lot of force to full length resize. I will have a very good look at the rest when they come out of the cleaner.
Brassman66
CGN frequent flyer
This only works if your Reloadet Ammunition is used only in one particular Rifle. If there is a Chance reloadet Ammo is used in different Rifles of the same Caliber, then the only way to go is full sizing.
Cheers
