7mm STW Dented cases & cracked above the belt?

Just curious, what are the measurements of base to datum before and after firing, and after firing and after resize. Also, how much expansion just above the belt on new, and fired case? rsbhunter
Can you get the seating stem and expander ball out of the die? If so I'd probably try to tap it out with a wooden dowel. If real tight you could soak in some penetrating oil and put it in the freezer. Then screw it back in the press and warm up the die with a hair dryer while tapping the case with the wooden dowel. If you have a brass punch that would work better. Good luck.
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I shot a few rounds today & everything seemed ok, chambered easily , no hard bolt life or extraction? When I got back home I decided I would resize the shells so they would be ready to load as I shot the rest. First shell I tried to run thru the sizer the head came off inside the dang sizer? I started to inspect the fired cases & noticed some big dents right below the shoulder & almost all cases looked like the were cracked above the belt wit black soot showing? They are Hornady cases & I believe that was there 4 loading and I had annealed them before loading. Some of the shells look like they have a very faint crack & some have carbon showing in the cracks, I`m surprised they didn`t separate when ejecting from rifle. What in the world is going on & any suggestions on getting the stuck shell out of my resizer die. Should I just scrap all the remaining brass that has not been loaded, I was well below max on all of them that cracked.
Case head separation (the crack above the belt) is a common problem in many cartridges that use a belted case. Because the belt prevent the entire case from getting into the sizing die the brass flows and tends to thin out just above the belt over multiple reloadings. I shoot and reload for several 300 WMs and this is one of the primary issues why I do not like Hornady brass. It just doesn't stand up to more than 3 or 4 firings for me.
Another tool that will really help you extend your belted cartridge case life is getting a Larry Willis Belted Magnum collet die. https://www.larrywillis.com/
This die will extend your case life because it pushed the brass back toward the belt to prevent it getting too thin. One end of it is a case gauge and after resizing my brass before priming I run every case through the case gauge side and any that will not slide down to the belt I then run through the die. I have found that about every third firing is when I need to do this. I use Winchester brass and commonly get 6 to 9 firings with the primer pockets being the only thing that eventually ends my case life.
I also recommend getting a good head space gauge. Larry Willis has a nice digital one that I really like. I use this to adjust my sizing die to ensure I'm only bumping the shoulder back slightly so as not to over work the brass.
Look up the Larry Willis collet die and do some reading on it.

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The above statement is also false.
The belt doesn’t need any sizing and it is NOT supposed to go inside the die.
The belt is adjacent to the solid part of the case head, the case walls do not start until .020”-.040” above the belt, the expansion line is plainly visible on all but Norma brass.
The expansion line is where the sizing takes place, not the belt.
The brass only ‘flows’ because the shoulder is pushed back too far by most reloaders, because they do not understand how to size the brass correctly.
This BS has been bandied about for so long that it has become factual….
There is only ONE cause of case head separation, which is EXCESSIVE HEADSPACE. The HEADSPACE of the belt can NEVER change physically, it is held to .220+.003”, that is the difference between a GO GUAGE and a NO-GO GAUGE. .003”!

So, if you continue to size a belted case excessively, just like ANY case, it will eventually split where the case isn’t held by the chamber during firing as it stretches REARWARD.
Larry Willis’ description of what happens is false, it always has been. Just more BS copied from some gun rag writer that knows nothing about belted cartridges.

That’s the last word I will say in the matter.

I agree that case head separation can only be caused by the case being stretched , caused by excessive shoulder set back, causing excessive headspace. I shoot 7 mag and have 5-6 reloads with no signs of insepient head separation. This is why F class and benchrest shooters only set the shoulders back .001-.002 . A belted case base to Datum line setback is no different than non belted. Accurate measurements are imperative to case life, as well as loads that stay within "sane" limits..rsbhunter
A Brownell's broken case expander may be just what you need to save the die. They are great for head separated case extraction in the rifle chamber. If your case is in the die really hard the collet may not have enough drag on the inside of the neck to get it out, but I bet it will work just fine.
the brass is being squeezed by the die , it will be difficult to remove at home .a chamber and die are not the same size , a sizing die must be smaller than the rifle chamber .
I have a 7stw and have been where you are. You're setting the shoulder back too far with the full length die.
Throw the die instructions in the garbage.
Measure the shoulder on a fired case.
Use a candle flame to "smoke" the shoulder of a fired case.
Set the fl sizer to just touch the soot on the case shoulder and measure.
You want only a cpl thou bump, and doing this will keep your brass from expanding too much at the belt.
Nosler brass has lasted 6x more firings than Remington brass and the primer pockets are still tight. I have also found that using a Redding competition die set, specifically the body die, that I no longer use the willis collet die. That body die can also set the shoulder back too far if you set it up to hit the shell holder, depending on your chamber dimensions.

Larry Willis does not claim to resize "the belt" in any publication I have seen. He resizes the case "from the belt" forward.

@WapitiBob youre right on. I had a 7rm decades ago that the die wouldnt size the case just forward of the belt. It looked a bit rounded rather than a square corner. With each firing, it got tighter until you just couldnt close the bolt. Sharpie that area of the case proved that is where it was hitting and causing the issue. I wish I had the Willis die back then. Im guessing that the back edge of the chamber where it meets the corner of the belt and body was over polished and slightly rounded and the die just couldn't get in the corner. It was the same as a neck sized case getting tighter with each firing.
Seebee, At some point I'll have to run my brass thru the Willis die, I just haven't gotten there yet. Once the guys in the 7stw forum got me straightened out and only having .002 shoulder bump my brass life went straight up. That belt is a non issue now.
Larry Willis does not claim to resize "the belt" in any publication I have seen. He resizes the case "from the belt" forward
I never said he does….what he does claim is that due to the die not sizing the belt, which is impossible because it is solid brass, that this causes the bulge.
What causes the bulge is a chamber that doesn’t fully support the case head, thin brass and oversized chambers.
It has nothing to do with the belt.
Coned breech chambers in certain rifles cause this bulge, Norma brass is notorious for this as the web is actually below the front edge of the belt…section a case and see for yourself.
The collet die addresses the issue, but it does not change any of the above if the brass is being oversized. As I said, I have never had any of these issues.
I load for 257 Bee, 264WM, 270 Bee, 300WM, 300 Bee, 338WM, 340 Bee & 375 Bee. I also load for 458 Lott, but that is a different kettle of fish.
If you bump .002” and, end up with .001” head clearance due to spring back, then all should be good.
Even a rimless case that is sized too much will exhibit incipient case head separation.
I have had my fair share with this on my 6.5x55, it was a known problem with the brass at the time, similar to how people are having trouble with 280AI and PRC.


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