.40 S&W Sizing Die Question

[IDescribe]

I'm about to start reloading for .40.  When I was shopping for dies, I saw some criticism of Redding .40 carbide sizing dies marking the webbing section above the extractor groove.  I did some further research, and it seems that Redding recommends that for .40/10mm, they recommend not adjusting the sizing die to touch the shell plate with their normal  sizing dies, carbide or not.  Their explanation is that with .40S&W, if the carbide ring is set up to size the base/head/web to the right size, it leaves the mouth too large for optimum bullet tension and increases the chances of bullet setback.  They say that has been a running problem with .40 from all manufacturers, and that their (Redding's) solution was to re-spec the carbide ring to size for proper bullet tension on the upper half of the case and advise not to do full case re-sizing.  If you do full-case re-sizing with these dies, it will overwork the lower webbing area of the case.   Redding has since released a "dual carbide ring" sizing die for .40 (and a few other straight-walled cases) that sizes the mouth and base with different rings, each to the proper size.  These seem to be out of stock everywhere I looked.

So here are my questions:

Is anyone familiar with this issue?

If this is true, might the under-tensioned, setback prone .40 sizing dies out there be responsible for the disproportionate frequency with which .40 suffer KB's?

Might using Redding's normal die and full-length resizing, over-working the webbing, result in weak webbing and KB's?

Might using Redding's normal die and not full-length resizing leave cases out-of-spec at the base and result in out-of-battery KB's?

If I could have found one of Redding's dual-ring sizing dies for sale, I probably would have bought it, even at the $90 price tag for the  one die, and never asked.  But that doesn't seem to be an option.

Any thoughts appreciated. 

[Wobbly]

I was using Redding dies for 40 up until a couple of months ago, but they were their standard dies w/o carbide. I've used those type dies on 40 and 9mm without problems, but I always lube the cases anyway. In fact, I count their standard 9mm dies set as one of the best.

While I believe your post, it leaves me with more information than I can digest. If they have trouble with 40S&W, then what happens when you use the same dies on the longer 10mm ? Strange. Very strange.

I don't think the sizing die should ever touch the shell holder, unless of course your ram doesn't have a stop and depends on that. I use a sheet of paper as a 'feeler gauge' to get as close as possible without actually touching.

 

[IDescribe]

Thanks, Wobbly.  Maybe I should have said Redding recommends not adjusting the die far enough down to full-length resize.  I haven't actually read the instructions myself, just reporting what others have said.   

As far as 10mm goes, I would have to think 10mm is the same way, them being as similar as they are and both straight-walled.  The thing that confuses me about it is that

If a carbide ring for a straight-walled case that sizes the web to the right size leaves the mouth without enough bullet tension, wouldn't that effect be magnified with a tapered case like 9mm?  Redding's statement seemed to indicate it was a problem specifically for straight-walled cases.  I don't get that.

For the record, Redding makes the dual-ring die for .40, .45, and several revolver cartridges.

[Wobbly]

Maybe I should have said Redding recommends not adjusting the die far enough down to full-length resize. 

That's proabably becasue the carbide ring can be shattered without too much trouble.  Just a kiss of the shell holder could be carbide death.

If a carbide ring for a straight-walled case that sizes the web to the right size leaves the mouth without enough bullet tension, wouldn't that effect be magnified with a tapered case like 9mm?  Redding's statement seemed to indicate it was a problem specifically for straight-walled cases.  I don't get that.

Yes, which is why I believe that 9's loaded using the less expensive carbide dies are likely to look like a coke bottle. Sometimes called "wasp waist". The obvious short cut for the die designer is to use a carbide ring with a single inside diameter, sized to hold the bullet. This is slid over the case, as far down as possible, which right-sizes the mouth, but undersizes the mid-section. Then when the bullet is seated, the mouth is expanded back out, but the mid-section is still undersized. Instant coke bottle.

 

[IDescribe]

I guess I'm going to go with their regular carbide dies and maybe get the GRx die to resize the base.

[motosapiens]

I've only ever used the regular old Lee carbide dies for 40, but I've loaded around 20,000 rounds of it in the last few years. I get a slight 'coke-bottle' shape to the rounds, and I like it. I get no setback ever under any circumstances, and everything feeds perfectly too. FWIW, i adjust the die the way the instructions say, IIRC that is just barely touching the shell-holder.

[IDescribe]

I should have put this in the first post.  This is not where my questions started, but a lot of what I said reflects this particular product description:

http://www.redding-reloading.com/index.php?option=com_content&view=article&id=124:dual-ring-carbide-dies


EDIT:  I'll go one step further.  EVERYTHING I said came from

1) descriptions of problems people had with Redding dies leaving a "band" above the extractor groove, which turned out to be the metal getting swaged
2) one person's discussion of a conversation with Redding about that problem, where they explained their instructions and reasons for  not sizing below the seating depth of the bullets, and
3) the above product description

[papaairbear]

I guess I'm going to go with their regular carbide dies and maybe get the GRx die to resize the base.

I don't know what press you use, but the Bonanza (now Forster) co-ax I have wont accept the 'push rod' base of a G-Rx in the shell holder since it's designed to slide into the shellholder slot on a ram.

[IDescribe]

Big Boss II

[jameslovesjammie]

I don't think the sizing die should ever touch the shell holder, unless of course your ram doesn't have a stop and depends on that.

That's probably because the carbide ring can be shattered without too much trouble.  Just a kiss of the shell holder could be carbide death.

This is the was I have always treated carbide sizers.  When the press cams over, it's amazing how much force it actually applies to the bottom of the die.  Carbide is harder, but more brittle than standard steel.  I've heard of several people "popping" their die from camming over carbide dies.