WHAT am I doing wrong? Seating die crumpling .357 Mag. cartridges

Doug.38PR

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I just went upstairs to load a dozen .357 Magnum cartridges as I have been the .38 Special loads (and YES I have been readjusting the die accordingly and as instructed the same way with the .38s) The first load that I adjusted the die with came out just fine (which you see by itelf). Then the three that followed were crumpled in the middle like they were being bent inside the die. I then tried to take a fourth cartridge and started over using it as a starting point (as I had with the first one that came out alright) and IT was crumpled too.
 

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Try backing off on your seating die to lessen the crimp.

I normally use a factory load to rough in the setting. Back the seating stem out and screw the die down until it touches the loaded round, then bring the seating stem down to touch the bullet. You can make further adjustments from there.

BTW, you probably still have it set for .38 Special that's .1" shorter than .357.
 
That's exactly what I did do. I took the stem all the way out and did just what you said for the .357 magnum cartridges. It was NOT adjusted for .38 Special. As I said, the first cartridge came out fine
 
The entire body of the die has to be moved up to conver .38 to .357, not just the stem, except for the sizing die..
I use washers for the bell and seating dies to convert .38 dies to .357 height, and leave the internal settings alone. I got the dimensionally correct washers from RCBS several decades ago, and they save a world of fiddling and guessing.
 
here's what I did.
I had the washer locked at my .38 special load. took a red marker and marked it. Unlocked the washer, backed the seating stem out. Put a cartridge in, raised it. started screwing the die in until it met the cartrige. backed it out a half turn. put a bullet in the cartridge in. gradually lowered the stem until bullet was seated as desired. backed the stem out. started lowering the die until bullet was satisfactorly crimped. lowered the stem until it met the bullet. Locked the die washer. That cartridge was fine. THEN, I put the next bullet in the next cartridge (and so on) and what you see is what happened. I had changed NOTHING on the die from the time that first good round was prepared
 
Well, there are a couple of things that can cause this

#1 too much crimp
#2 inconsistant case length
#3 not belling the case mouth before loading

Plus it looks like the bullet is not seated to the cannelure, I shoot for the middle of the cannelure but thats just me. If you are seating them outside of the cannelure, then you will need a taper crimp die and not a roll crimp.
 
Doug, that die does two jobs. The stem seats the bullet BUT the outside of the die puts the crimp on. The outside of the die is hitting the case, it is .110" longer than a 38spl, and causing the problem.

Do this, screw the seating stem all of the way in and then loosen the lock ring and adjust the die so the bullet is seated correctly. Screw the stem in ALL of the way. You will have to back out the whole die then.

There is another step to this, and I will tell you what to do after you alleviate the case buckling.

Maybe I will make a video so you can see what I mean. Are you using Lee dies? If so, go to their website and watch their setup videos. A lot of help.

You could PM me your phone number and I can talk you through it too. Either way.

Remember, this is just the first step, more to come..................
 
Is it just me or are the bullets seated with the cannelure completely above the top of the case? The photos are blurry but if that is in fact the case and you are trying to crimp into an area of the bullet with no cannelure, you will buckle the case.

I would start over with a properly sized, expanded and flared case.

1. completely raise the seating stem.

2. raise the die body until it is nowhere near touching the case mouth with a case in the shell holder and ram raised completely. At least two full turns above the point where the die body touches the case mouth.

3. place bullet in the case & raise ram completely. Then lower the seating stem only until it just touches the bullet.

4. lower ram and then adjust the seating stem only down to seat the bullet into the case. Go one full turn at a time, alternately lowering ram to inspect the progress, adjusting the stem only downward and raising the ram. Repeat until the bullet is seated to a point where the top of the case is near the top of the cannelure. DO NOT take any COAL dimension into consideration-you want the top of the case mouth near the top of but not above the cannelure.

5. after the bullet is fully seated as described in step 4, lower the ram and run the seating stem all the way up again.

6. Now, raise the ram with the case w/ seated bullet completely to the up position. screw the whole die body without touching the seating stem down until it touches the case mouth, then lower the ram and turn the die body down one half turn. Raise the ram fully, then lower and inspect the crimp. If more crimp is needed, screw the die body down another half turn, raise the ram and then lower and inspect. Remember to make no adjustment to the seating stem. Keep repeating until the necessary crimp is obtained-then, with the ram down, lock the die body in place.

7. Raise the ram with completed round completely and, with it up , screw in the seating stem until it touches the bullet. The die body should not be moving while you adjust the seating stem.

If the cases are buckling on straight walled pistol cases, you are crimping with the case mouth outside the cannelure (or crimp groove on a cast bullet), crimping too much or pushing the bullet down while the case is crimped. Do not fool around with any kind of marker, etc.. Instead think about how both parts of the die work and how the adjustments you are making affect the work you are performing. You need to resign yourself to the fact that you will need to readjust the dies when switching from .357's to .38 specials and after you learn how the adjustments work, it will become 2nd nature to you. The Lyman reloading manuals used to have excellent drawings showing sectional views of the dies during the loading process and these made understanding that process quite easy. I do not know if the latest versions still contain this info or not.

Bruce
 
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Doug I feel your pain, I had the exact same problem when I was reloading some .41 magnum with 210gr Hornady XTP-HP bullets. I had no problems moments before reloading some Sierra 210gr bullets. When I switched to the Hornady bullets I got crumpled cases. I fixed the problem by simply seating and crimping in two seperate stages. It is a PITA but I couldn't risk losing any more cases as I was low on .41 mag brass at the time.
 
As already mentions RCBS and maybe someone else makes a spacer washer the correct thickness as the difference between 38 and 357 case length. If your gonna load both with the sames dies it will be the best couple bucks you ever spend on reloading equipment. Simple set up your dies for 38 cases, then use the spacer under the expander die and seating die for 357 brass, assuming the same bullets are being used. If different bullets are used you may have ti tweek the seater stem. Spacer not required on sizer/deprimer die. This won't solve your current problem but will prevent it in the future.
 
The only thing I can add to this at this point is maybe try opening the case mouth just a little more. The neck may just have too much tension from resizing and the case walls buckle from the friction of trying to get the bullet started and then give out as it goes deeper. I don't know that it will help, but add some polish to your media. I add a small squirt of Nu Finish to fresh corn cob. It leaves a thin layer of the polish on the cases. That might also help the bullet slide into the case, but I won't swear to that. The logic is sound, but the reality might not support it. And I highly second buying the washer from RCBS or where ever. Or just do what I did after even the washer became a part to keep up with, just buy a second set of dies. I leave mine locked in the turret head and didn't feel the need to keep dinking around with the washers and settings.
 
The first thing I tried before even posting this thread was belling/widening the mouth of the case a little more (it even looked a little too much to me) and that didn't work.

The cannalure brings up another point. I was shooting for right at the base of it. The first round, as said, did fine. But the rest, that became crumpled in the middle....crimped just below the cannalure as though the bullet wouldn't seat all the way down where I had it.....almost as if it crimps it before the stem has completely seated the bullet (but why would it do that on the following four and not the first one?)
 
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The crimp actually starts before the bullet is completely seated. The crimp and the seating actually end at the same time. As a last resort, you can back off the seater die body and set the seating stem to correctly seat the bullet. Go through all your cases seating the bullets. Then back way off on the seater stem and adjust it to just crimp. A lot of crimp is not needed unless your loading hot loads with slow powder. All you really need to do is remove the prior belling of the case mouth and maybe just a touch more.
 
Doug-
We aren't there, you are. Scrap what you have done, and go by previous posts . We are trying to assist from afar!
As you claim to have done so, don't use your factory round to set up the die unless you are using EXACTLY the same components for your handloads. Different style bullets for the same maker are likely to have the crimping groove located differently.
DON"T aim to crimp at the "bottom" of the crimping groove, aim for the middle. do this by setting the bullet depth first- back the die out of the press so there is no chance of the crimping feature coming into play. Adjust only the seating stem downward incrementally ( checking your progress each time) until the bullet is far enough into the case for the crimping groove to be in line with the edge of the casemouth ( try for the middle, NOT the bottom edge) . BACK the seating stem out ALL THE WAY, and start to set the crimping feature. Screw the die down into the press ( with the cartridge in the shell plate or shell holder, raised up into the die) . You will feel when it touches inside ( the die will meet resistance as you screw it into the press ). Lower the ram, and screw the die in a LITTLE bit more. Raise the ram. Check how it looks- DO NOT OVERCRIMP. Too much crimp gives the brass no where to go, and the case will deform as yours have. We have ALL done so, when we started out.
If all else fails, read the manuals. There is stuff in them that we all need.
 
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I've had this problem a few times and it was always a case of too much crimp. I've been able to salvage the crumpled rounds by running them through the Lee Factory Crimp Die which resizes the case.
 
Doug-
As you claim to have done so, don't use your factory round to set up the die unless you are using EXACTLY the same components for your handloads. Different style bullets for the same maker are likely to have the crimping groove located differently.
.

I'm sorry for the confusion. I wasn't using a factory round, I was using a reload that I reloaded and used to set the die and stem. Put the bulletless cartridge in, raised it and started screwing the die in (stem out) until it met the cartridge, backed the die out a half turn, put th bullet in the cartridge and then raised it and lowered the stem until I was satisfied with the seating of the bullet. I then backed the stem back out and then started screwing the die itself in until I achieved the desired crip. Then I screwed the stem back in until it met the tip of the bullet (and locked both the stem and the die in those positions). That one bullet came out fine. I then tried seat and crimp the next four with that setting (and got the bad four you see in the picture)
 
.357's take a lot of crimp to prevent setback due to recoil. If you seat the bullet and crimp in the same stroke, the press pushes the bullet another 0.05" or so after the crimp starts to engage it. At very least, that will shave lead (or bronze), and at worst you will buckle the case.

The only sure solution is to seat and crimp in separate operations. That's how progressive presses work.

My RCBS .357 dies came with a 0.1" washer, so you can use the same die for both .38 SPL and .357 Magnum without resetting the die. I put that under the nut when seating the bullet. Then I remove the washer and back off the seating pin and crimp the cases. The bullets are held tight enough before crimping that they don't move with normal handling.

The only time I buckle a case is if I get it crooked on the ram, or the bullet is not quite straight before seating. The amount of force needed to crimp the bullet is much, much less than if you do both operations at once.

The bullet should be seated as to not exceed the maximum OAL specification. With jacketed bullets, the crimp usually falls in the middle of the top cannelure. With cast or swaged bullets, follow the manufacturer's advice.
 
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Well, don't shoot 'em, lol!

Something that I like to do is process the brass separately from the loading--so decap, size, bell and then later prime, charge, seat. I'm not sure that would help your particular situation, but whatever.

.38s and .357s are my favorite rounds to load--very rewarding.
 
but why would it do that on the following four and not the first one?
That first cartridge was the only one you seated in increments, a little at a time instead of all at once, like the next four. You have the die set for too much crimp. So, go back and set the rough setting like I said before. After that, set your seating depth. Then adjust the crimp down, if that's what you want, but you'll have to back off of the seating stem to set the crimp. All you really need is to take the flare out of the case, if you have sufficient "neck" tension. When the crimp is set, screw the seating stem back in to where it touches.

Set your flare/bell/expander to where the base of the bullet will just start in the case. Don't over do it or you'll reduce neck tension too much.
 
Doug,
Paul has given you the next step to get this figured out. He also has given you a possible reason for your first round, I concur.

Now, did you go to Lee's website and watch the video for proper die setup?
 
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