Pass through sizing

[Vee_Kay]

The shadow introduced me to the pass through sizing.  I've run all my 10mm empty brass through, and I'm starting on some .357 sig, as they both have the same base diameter.  However, I could almost squeeze an ornery mule through that factory crimp die more easily than those .357 sig casings.  Someone have an idea why they are taking so much more pressure?

[sqlbullet]

Could be a looser chamber allowing more case head expansion.  It could be higher pressure loads doing the same.  It could be just the spec the brass was built too.

Put some calipers on the brass of the 10mm before and the 357 sig before.  Let us know the results.

[DM1906]

If they were fired from a Glock barrel, they are excessively bulged.  Either get a closer look at the brass, measure the rim and base, and confirm they aren't out of spec.  If they are, toss 'em.  This isn't uncommon with high power reloads.  If they are usable, try some sizing lube.  Some cases are just tough going.

[sqlbullet]

Imperial sizing wax will work wonders you can't imagine.

[The_Shadow]

The CCI and Speer 357Sig are the toughest to size and they have a smaller flash hole that can break you deprimer pins.  I actuall had to drill mine out to equal other brands!

Be sure your Die is as far up on the stroke that will still let the bottom of the case pass thru the carbide ring of the LEE FCD for the most leverage of your press.  Yes some lube will help!

The CCI & Speer 45ACP were also tough to run thru that sizer also, something about that brand especially in the area of the extractor rims.

[DM1906]

Also note, the FCD is NOT a sizing die.  You should be sizing them in your die set sizing die.  It's usually best to size/decap first, then run them through the FCD to clean up the lower case where the sizer doesn't go.  If they're still tough going after sizing, you might have some excessively expanded cases (aka: junk).  Measure.  Measure.  Measure.  The FCD is a modest chamber diameter, NOT published cartridge case diameter (like the sizing dies).

[sqlbullet]

Also note, the FCD is NOT a sizing die.  You should be sizing them in your die set sizing die.  It's usually best to size/decap first, then run them through the FCD to clean up the lower case where the sizer doesn't go.  If they're still tough going after sizing, you might have some excessively expanded cases (aka: junk).  Measure.  Measure.  Measure.  The FCD is a modest chamber diameter, NOT published cartridge case diameter (like the sizing dies).

I learned this the hard way after spending an afternoon thinking my crimp die had gotten wonky.  Finally figured out that the regular sizing dies was not an optional step after running them through a pass through die.

[The_Shadow]

I don't size mine prior to the FCD used as a "pass-thru" die, and placing any of the "pass-thru" sized casings in the cartridge gauge will show them fully sized to fit it!  Yes you can size/deprime first then run them afterward in the "pass-thru" or just size them in the "pass-thru" setup!

What he was seeing is probably what I noticed with CCI/Speer cases mostly (40S&W/357SIG/45ACP), they are slightly larger at the extractor rim (thus tighter fit as they are being squeezed down).  Afterwards you can see a polished looking shine where they were tight, usually the rim and the very thickest part at the start of the extractor cut/bevel.

TIP; I place a piece of card stock (3x5 card) rolled and cut to fit inside the FCD to keep cases from grabing the threads inside!

[sqlbullet]

That trick with the carboard is a good one.  Another I have is to get a costco nut container and drill a 7/8" hole in the lid, then it can be threaded on the top of the die as an extra capacity sized case holder.

[DM1906]

I don't size mine prior to the FCD used as a "pass-thru" die, and placing any of the "pass-thru" sized casings in the cartridge gauge will show them fully sized to fit it!  Yes you can size/deprime first then run them afterward in the "pass-thru" or just size them in the "pass-thru" setup!

What he was seeing is probably what I noticed with CCI/Speer cases mostly (40S&W/357SIG/45ACP), they are slightly larger at the extractor rim (thus tighter fit as they are being squeezed down).  Afterwards you can see a polished looking shine where they were tight, usually the rim and the very thickest part at the start of the extractor cut/bevel.

TIP; I place a piece of card stock (3x5 card) rolled and cut to fit inside the FCD to keep cases from grabing the threads inside!

If it works for you and you have no recurring issues, more power to ya.

However, I do not recommend this for any cartridge.  I stopped using cartridge gages years ago.  A cartridge gage is only a chamber without a barrel, most often sized to the SAAMI chamber spec.  This is very different than the cartridge spec, or a properly sized cartridge case.  Your process would be similar to neck sizing rifle cases, for single-shot match or a case that's dedicated to only one rifle.  The FCD isn't a sizing die, and I don't recommend anyone use it as such, especially someone who is less experienced or just a beginner at handloading.  I think this applies to many, if not most readers.  We, as experienced handloaders, have a responsibility to inform new(er) handloaders of the fundamental techniques, and be aware that a discussion between the experienced may be understood as the proper way to do things.  This can lead to disasters.  If we had control over every reader's complete loading procedure, their component selection and inspection, and every firearm they will ever use the ammo in, things would be very different.  We don't, and we can't.  I've introduced dozens of beginners to handloading, and always find it difficult to leave out my shortcuts and bad habits, but I do.  I see a lot of really bad advice being issued to beginners, and all I can do most of the time is just shake my head.  I hate sounding like the Poindexter in the room, but a lot goes unsaid, and this stuff can be lethally dangerous, even under the best of conditions.  One example (don't remember which site), is someone "instructing" and encouraging beginners on how to start casting bullets.  I'm sure the OP meant well, but it was one of the most irresponsible suggestions I've seen in a long time.  Simply get a pot, put some wheel weights in it, stick it on a fire, start pouring your mold.  No mention of any inherent dangers of the process.  Where's the accountability?  Who's responsible when something goes real wrong, and someone's house burns down, or someone's kid gets injured, or worse?  It's like instructing someone on the proper application of Russian Roulette.  When you send someone off to rely on luck, eventually they'll run out of it.  Even if we began every post with a disclaimer, it wouldn't matter.  Not everyone is born with common sense, and most people don't read them anyway.

No apologies if I've offended anyone, although it is never my intention, nor was this directed at any specific individual.  If you feel this reply is wrong, tell me and I'll delete it and move on.

[Vee_Kay]

To clear up a few things, The majority (90%+) of my .357 sig casings have a SPEER headstamp.  All were fired through a Sig P226 that came as a .357 sig. All have been resized in a Hornady .357 sig. resizing die.  My problem began when I purchased a Glock 22 (40 S&W) and purchased a Lone Wolf .357 sig.  drop in barrel.  At that point my reloads didn't chamber in the new barrel, requiring a bit of a nudge to the slide.  Since I was having a little bit larger problem with my 10mm feeding into a new Lone Wolf 10mm 4.6" barrel in my Glock 20C.  I though I'd try the Shadows solution on my .357 sig.  Being naturally lazy I posted before I went to my manuals and discovered actually the base of a 10mm is a .001 larger than a sig. casing.   When I did run the sig through it almost seemed like they were catching on something in the FCD die and bulge buster.  I put a very small amount of case lube on them and they started going through as easily, or even easier than the 10mm.  (I need to try the aforementioned trick of the card inserted.)  One very important point I discovered is if using the pin from the bulge buster kit, DO NOT mistakenly feed your .357 sig through UPSIDE DOWN.  The case inserted itself very tightly around the pin requiring destruction of the case to get the pin back to operational order.

[The_Shadow]

I would advise anyone reloading 10mm, 40S&W, 357Sig and 9x25Dillon view the Cross Section of a SMILEY sticky...
http://10mm-firearms.com/reloading-10mm-ammo/cross-section-of-a-smiley/
Some cases are NOT RELOADABLE or REPAIRABLE!

Yes the Push Pin from the LEE Bulge Buster Kit is for multi cartridge use, 9mm, 380, 40, 10mm and 45ACP.  Its diameter is such that it will push the smaller cases up into the FCD Dies for the appropriate FCD cartridge die.

The pin is normally used to push the casing on it headstamp/primerd end up and thru the bottom of the FCD's carbide ring inside.  Working at the very upper most part of the press stroke takes full advantage of the leverage applied.

The FCD for 10mm/40 S&W is used as a "Pass Thru Sizer" for the straight section of the cartridge, why does it work?  The carbide ring in the very bottom of these dies are dimentional set at the sizing size for these cartridges.  It will make them recondition all parts that it comes in contact with as the casing is pushed straight thru. 

The FCD for 9mm Makarov works for 9mm as a pass thru and the FCD for 380 & 45acp like wise will size those.

DM1906, Im not making this statement as a jab or dig on your statement, mearly stating facts here...
Cartridge Gauge is not the same as a barrel's chamber period!  As a matter of fact most chambers are cut larger than this spec for more reliable feeding.  But the gauge helps to insure that the ammo will be at a spec where it will fit any chamber, including the tightest ones.

[DM1906]

............

DM1906, Im not making this statement as a jab or dig on your statement, mearly stating facts here...
Cartridge Gauge is not the same as a barrel's chamber period!  As a matter of fact most chambers are cut larger than this spec for more reliable feeding.  But the gauge helps to insure that the ammo will be at a spec where it will fit any chamber, including the tightest ones.

I didn't say it was the same as a barrel's chamber.  I said, "A cartridge gage is only a chamber without a barrel [a rough description], most often sized to the SAAMI chamber spec.".  Most firearm chambers are quite larger than the SAAMI spec for chambers in some respects (Glock is a prime example), which is a minimum dimensional measurement, with a +/- of a specific value.  Unless your gages are custom, or really poor quality, they should be SAAMI spec.  SAAMI cartridge specs. are quite the opposite.  This is done to ensure that every mfg, be they firearm mfg's or cartridge mfg's, produce products that will work with one another, universally.  This is why I suggest not using the FCD for case sizing, which sizes more closely to the chamber dimension, rather than the cartridge dimension.  This affects case volume and combustion pressure.  It also introduces inconsistencies.  Your use may be unique, and you have the experience to make that determination.  My response only applies to those who may not know, or don't have the experience they should have to know.  Case gages for straight wall cases are essentially an unnecessary expense.  Dimensional measurements are very simple, and only involve two values, 3 at most (if a taper is involved, such as 9mm Luger).  Shouldered cases are different, and a gage should be used if loading for multiple chambers, or recoil operated actions (.357 Sig, for example), to ensure proper head spacing.

[The_Shadow]

Oh, OK I understand better what you were trying to say. 

[REDLINE]

Maybe I'm off base here, but I don't believe SAAMI specs are limited to a minimum dimension, I think SAAMI gives a range of measurement that anything applicable should fall within.