Hornady 6.5 max die splitting

New to reloading I thought slight cam over was proper way to set up die
Just to belt and suspenders this.... what press and what brand shell holder are you using?

Not all presses are designed to "cam over" meaning there is a point where the ram actually drops slightly at the end of the stroke. If you have a hard stop press you could very easily be putting way too much pressure on to the die trying to "cam over" something that can't even do it.

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Even if you do have a press that actually can cam over, then also there's a question of is the shell holder short enough to let the die go all the way down the case. I'm not saying this is common by any means, but it's not unheard of to match a a tall shell holder with a long die and not be able to size a case fully without putting the die into solid contact with the shell holder. I usually use a shell holder of the same brand as the press, but will mix and match sometimes - the important part is the keep the shell holder you set the dies with with the dies and always use the matched set so that the die/ram interface point isn't getting changed unintentionally.
 
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Just to belt and suspenders this.... what press and what brand shell holder are you using?

Not all presses are designed to "cam over" meaning there is a point where the ram actually drops slightly at the end of the stroke. If you have a hard stop press you could very easily be putting way too much pressure on to the die trying to "cam over" something that can't even do it.

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Source:

Even if you do have a press that actually can cam over, then also there's a question of is the shell holder short enough to let the die go all the way down the case. I'm not saying this is common by any means, but it's not unheard of to match a a tall shell holder with a long die and not be able to size a case fully without putting the die into solid contact with the shell holder. I usually use a shell holder of the same brand as the press, but will mix and match sometimes - the important part is the keep the shell holder you set the dies with with the dies and always use the matched set so that the die/ram interface point isn't getting changed unintentionally.
Amen brother.
 
So if I'm using Redding competition shell holder should I just barely touch shell holder to the die
 
So if I'm using Redding competition shell holder should I just barely touch shell holder to the die
I would suggest you buy a standard shell holder for now. The competition set has a very specific purpose in adjusting shoulder bump as case shoulders harden over the lifecycle of the brass. There are several different ways to use the set (one of them involves using a standard shell holder, that's why I said to get one), and you might not be to the point where you need them yet if the shoulders of this case design need to be allowed to grow for a firing or three.

One critical aspect of case sizing is to first let the case GROW fully. It sounds counter intuitive because of course we have to size cases to fit them back into the chamber, right? Try rechambering a fired case after it cools down... if it fits, why do we need to resize it? There are reasons (like sizing the neck down so it holds a bullet again), but overall chamber fit isn't a reason because we just proved a fired case slips right back into the chamber. It's because the case hasn't actually lengthened fully to fit the chamber, and (in the context of loading for accuracy and precision) you need to let it fully form to your chamber and keep it close to there instead of squeezing it back down to the minimum spec that Hornady cut their die to based on the case designers specs.

How you accomplish this is (in this case of a non-cam over press) for the first resizing of a fired case you should intentionally set the die well off the shell holder, and size the case until about half to 2/3rds of the neck is sized. The way I normally do this is I just don't screw the die in very far. Screw it in to touch the (standard) shell holder, back it off 2 or more full turns, size a case and look at how much of the neck is being sized, screw in until at least half the neck is sized, then test fit in the rifle. This works well for me when cases need to grow, which I believe based on what we've talked about so far is the situation you're in now.

When I say test fit in the rifle what I mean is reinsert that partially sized case into your rifle. If the bolt closes without resistance, the case isn't fully formed at the shoulders and you need to fire it again before you start trying to do anything to the shoulders. If you do size down to the point that the shoulders move on cases at this point in their life you will never know the full size of your chamber, and you'll end up shortening brass life by overworking the cases every sizing.

Once you finally get enough firings on the cases and they're at the point where the bolt WON'T close on a partially sized case - you've reached a point where the cases have grown to the full length of the chamber and you can start bumping shoulders. This is where the comp shell holder set is going to come in to play finally.

Put in the 0.010" shell holder, screw the die down until it touches the holder, and size a case. Does the case fit? If yes, that's all the bump you needed on the shoulders, fire the cases again. If it doesn't fit, grab another case (don't keep working the same case over and over during this), put in the 0.008" holder and screw the die down until it touches that holder, and size the new case. Does that case fit? If yes, fire them again; if no, move down a shell holder. Go until you find a sizing step that fits (using a new case each adjustment of the die).

Now here's what I do - I use the standard shell holder and put the comp set away at this point. The die is set up to touch a taller shell holder, so by swapping in the standard I open an air gap between the ram and die so there's no pressure put on the die other than through the case. This is because my press doesn't cam over - if I had a cam over press I would use another process entirely based on hard contact between the die and comp shell holder.

Eventually if you never anneal, your cases sized at the current die setting will stop fitting, so you put in the next shell holder down, screw the die down that much more and repeat the "does it fit" steps. Because the case hardened over multiple sizing cycles we had to bump "more" to make them fit - what's really happing is the brass springs back more so we had to make the die size tighter on the case to make it smaller so when it springs back it goes back to the old bump spec.

If you don't have a headspace comparator kit I would recommend that you get one because you can actually measure the shoulders during this whole process - find how much a case grows on a firing, how much the die does or doesn't move the shoulders, and when you get there you can measure the 0.002" bump change between the shell holders as you size cases down:
Amazon product ASIN B000PD5VN8

We'll call this theory of case sizing up there "Step 2" on my continuum of learning to size cases:
  1. Size all the way back to minimum every time to get a handle on the whole "don't blow up the rifle" thing
  2. Start letting cases grow and start sizing back as little as you can.
  3. Size so little you start having function problems, so go back to sizing more again to get function back
  4. Cycle between 2 and 3 until you're ready to do some learning and testing
  5. Start tuning case sizing practices:
    1. Use bushings or honed dies
    2. Use bump dies instead of FL/body dies,
    3. Use mandrels instead of buttons
    4. Start annealing
    5. Eventually buy a Lee collet die because at $20 why the heck not
      1. Buy multiple pins for the collet die, wonder why you didn't use these $600 of dies ago
    6. Try multiple brass brands
    7. At some point go through your "none of this even matters" phase and size everything with a $15 Lee FL die and seat with a hammer seater because you clicked in on some other tuning process and made a big leap forward
  6. Finally find something that works...
  7. ...but you burned out the barrel
  8. So start all over again, but this time skip ahead past Step 1 as far as you can based on how much you learned the last time through
  9. Go through this same type of multi-step learning and growth process with:
    1. Barrels
    2. Bullets
    3. Presses
    4. Scales
    5. Powders
    6. Tools
    7. Calibers
    8. Scopes
    9. Stocks
    10. Triggers
    11. Etc etc etc
  10. Repeat until your wife decides which rifle to bury you with
 
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Like the others that is the first time I've ever seen something like that, kind of crazy. It has to be a problem with the heat treating of the die. There is enough steel there to probably form a solid brass rod into a case. As for cam over that would be compressive force, so if anything it would damage the threads not split the die unless you were running steel into it. At any rate again there's enough metal there that you would probably bend the handle on the press before you would do anything to the die.
 
Cool just got done watching that
Pay attention to the Hornady guy saying (more than once) "reset the case to the SAAMI minimum." This usually means excessive resizing (0.0010 or more) of the fired case, resulting in decreased case life and reduced accuracy.

Getting better case life and accuracy entails resizing fired rifle cases having a shoulder enough to chamber in the firearm in which it was fired and no more: 0.002 - 0.004 or so. Doing so requires a decent micrometer and a case gauge set (Hornady makes a decent one).

Google 'bumping the shoulder' You should find multiple YT videos and or forum discussions, here and on other forums. Here is one of many.
 
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