Advanced 9mm leading troubleshooting - question on modified dies

Some of you guys may remember in the past couple of months that I posted a thread about trying to eliminate leading in my M&P 9mm, using the Lee 124gr .356 TL mold and air cooled WW alloy, with red HF powder coat.

I said I had already ruled out the following things:

-Undersized boolit
-Cases swaging boolit upon seating
-Too much pressure causing gas cutting
-Too little pressure causing failure to obturate

This led me on a wild goose chase where I was making sure my powder coat wasn't over- or under-cured, I wasn't using too fast of a powder (Bullseye vs W231), and I was looking into just buying a different mold (tried some samples of the Lee 105gr .358 SWC for example).

Long story short, I was wrong about being undersized. I was measuring with calipers and they were off. I recently obtained a micrometer and cast 4 boolits from each cavity on my 6-banger mold so I could get an average boolit size for each. Most were dropping right around .355". There's my problem.

So in addition to WEETing the mold (all 6 cavities are now sized to a uniform .359"), I have done some reading on Lee carbide 4-die set dies. I think the reason I wasn't getting bullet swaging when I seated or crimped is because the bullets were roughly the size FMJs or plated bullets anyway. But now I know there are two major dangers for swaging my not-extremely-hard bullets, which I can now confidently say will be .358" after casting, powder coating, and sizing:

1) The neck expander die with the stock 9mm plug in my die set is famously not long enough, so even a stiff case mouth will likely swage the boolit down when I'm seating. I went ahead and ordered the 38 S&W expander plug that I can drop into the die in place of the stock 9mm Luger one, as I found lots of people having success with that method elswhere on the forum. I have also ensured I set my die body up as far as possible in the press so the seating die isn't doing any crimping, and I can save that operation for the next die entirely.
2) The Lee factory crimp die famously contains a ring of carbide that smashes your entire cartridge and whatever is in it (like, say, an oversized cast boolit) down to small enough to always chamber. Guess that explains why I never failed a plunk test, even when using .358 105gr SWCs. I'm looking into three options to ensure this doesn't happen and I can make sure my bullets are actually at .358" when I fire them:

a) Punch out the carbide ring entirely.
b) Grind out the ring using medium grit valve grinding compound on a 9mm casing so that the ring isn't sizing anything down smaller than .361" or .362".
c) Use a different die. I'm looking at 2. This one is a standard non-collet taper die which does not appear to have a factory crimp-style carbide sizing ring. Anyone having success with it? This style looks even better, as I guess collet style dies crimp more consistently regardless of brass length. However, this collet style doesn't come in 9mm. Any chance I could get a 357 Mag die to work as it's roughly the same diameter? Or would the difference in cartridge length between 9mm Luger and 357 Mag make this a no go?

I'd like a collet style most likely unless people are having crazy success with the standard taper crimp 9mm die. Can anyone recommend me one?

Thanks in advance!

My experience mirrors yours. In the last 20 years I've sized to .358, lubed with moly grease and never looked back. If there's an issue, it's my handguns oozing bullet lube from every pore, the smoke and filthy hands. I've tried tumble lubing without success...

Thinner brass will help them fat bullets chamber more easily. Winchester 9mm is good thin brass.

I am not going to say I have had crazy success with the plain taper crimp die, but well before the internet I started reloading for the 45 and many others. Having reloaded all these years and many different semi-auto rounds, I still have never needed anything other than the standard taper crimp die, and do not seem to have ever had many of the issues some experience with the common 9MM cartridge with cast bullets. Nor did I even know what a "plunk" test was until I joined this forum.

The only factory crimp die I have and use is for the 223 due to the rough handling of the semi-auto rifles.

Regarding the "post crimping sizing die"; toss it. I have reloaded 9mm since 2004 and 45 ACP since 1988 and have never had a need to size my finished rounds. As a matter of fact, I don't crimp my semi-auto ammo, I use use a taper crimp die to remove any flare. If my ammo does not pass the plunk test I find out why and fix it.

I can recommend the collet crimp dies for revolver and some rifle rounds but IMO, it is not necessary for semi-auto ammo. With properly adjusted dies a plain old taper crimp, like the one you linked, will be fine. I had an FCD for my revolvers but it ruined some carefully sized bullets so I punched out the carbide ring and the resulting crimp was no better than a regular roll crimp so I went back to my Redding Profile Crimp. It now resides in a landfill some where in So. Oregon.

The only "neck expander dies" for handgun brass I know about are just to flare the case mouth to make bullet seating easier; reduce shaving lead. They are adjustable so I don't know how one can be too short. I have used M dies and they work but for my cast lead bullets I prefer a plain flaring die (like Lee's Powder Through dies) and nope my cast bullets, approx 10-12 BHN, are not swaged down in either 45 ACP nor 9mm...

This works for me.
Size boolit 1 thou over bore (12-15 bhn)
lee powder through expanding die
seat and crimp just to where the boolit doesn't move in the case when pushed against the bench
Lee factory crimp die - raise the ram, screw in die until it touches lower ram, screw in die 1/10th (apr) of a turn.

YMMV

I ground the carbide ring in my Lee .44 FCD, so it can be done. I think I used medium diamond lapping compound, as the SiC stuff for valve lapping will not be hard enough. I don't have a problem making some as cheap as Lee dies work for me with a little adjustment.

Hmm, the only abrasive compound I have is silicone carbide.

As I have no plans to load non-cast lead bullets with my die, I'm actually thinking it's probably easier to just punch out the carbide sizing ring in the FCD entirely.

For those asking; when I say Lee neck expander for 9mm, I mean the powder-through flaring die that comes in the 4-die carbide set.

After loading up a few dummy rounds and crimping per my usual procedure, I pulled several bullets and re-measured. They were .3585" before seating. After seating, crimping, and pulling, they were .357". Definitely swaged. To be fair, I don't know if it's my seating, the carbide sizing ring, or the taper crimp operation itself that did the swaging; I'll need to separate these out and test some pulled bullets individually. But the carbide ring is DEFINITELY where I felt the most resistance while making the dummy rounds.

Yesterday I spent a good 20 minutes trying to get the carbide sizing ring out to no avail. I put a 9/32 nut driver down the top of the die with it mounted in the press, and started hammering away. Tried light taps all the way up to fairly heavy hits, and I don't think it budged a fraction of a millimeter.

Anyone have recommendations on how I can get this thing out? I'm not concerned with preserving the carbide piece, so if it gets ruined in the process, that's fine by me. Just want the die to still work normally after the surgery ;)

After some more testing, my cases are swaging my .3585" bullets down to .357" anyway, even without ever touching the FCD. I suspect the FCD will still need its carbide sizing ring removed, but apparently I need to wait for my 38 S&W expander plug to arrive for my powder through expander die before I can even hope to get a .3585 bullet seated without swaging down.

One thing I found with loading 9 mm was my Dillon sizer die was so tight it added to the swagging problem, so I got a Hornady die set this problem went away.

I knocked the carbide ring out of a Lee .44 spl FCD die after grinding some off the bottom, it didn't take much effort.

I don't crimp my semi-auto ammo, I use use a taper crimp die to remove any flare I got the 38P Lyman M expander that works fine.
The 9mm problem - tapered case wall. cases work well for 115 factory stuff but not the heavier cast that is seated deeper. Longer expander is needed - sometimes the case bulges toward the head and the taper crimp die can remove that bulge if it is the right size. Other problem is 9mm barrels are all over the place size wise. 3585 seems a bit large. My XDs takes 357 boolits fine. Aftermarket barrel may be the cost effective choice?

The Lee taper crimp die works wonderfully in 9mm. No carbide ring, and you can adjust just enough to take the flare out and no more

Loading the 9mm luger with cast boolits is not for the inexperienced loader.
After loading for 45+ years my Dad gave me my first 9mm , a Walther P38, it wasn't too much trouble to load for but the new 9mm's , compacts especially ,
gave me fits....I actually cursed the 9mm more than once. It's a little stinker.

As for crimps...there are two, taper crimp and roll crimp. Taper crimping is considered crimping, how much crimp is up to you.
Gary

Yeah once I get the carbide ring out of my FCD, I'm only interested in using the taper crimp die to remove belling around the case mouth; not actually wanting to "crimp" per se.

I'm really hoping the new expander plug for my powder-through-expander die will size the neck of my brass out wide and deep enough not to swage the bullet when it is seated. If it doesn't, I may need to look into a new full length sizing die entirely, which I would like to avoid.

My M&P 9 barrel has a very narrow throat so 0.356" bullets fit with zero clearance. That means any part of a bullet that is wider than 0.357", it will give resistance to the slide closing smoothly. If I load the unsized and powder coated Lee 356-120-TC to where the cone meets the rim or use the TL-356-124-2R, then there is no part of the bullet that can jam into the throat

https://images3.imgbox.com/31/bb/pjN5DBP3_o.jpg

The M&P barrels also tend to have a tight chamber so using an "M" die with a fat bullet also could cause chambering problems. I don't have an "M" die but I made a poor man's version with the Lee 38 S&W expander stem which expands deeper than the 9mm expander and is longer than the 38/357 expander so it can reach the short 9mm case. With all that and a light taper crimp (no FCD), both bullets shot very well with zero problems in the M&P and also in an XD9 and 92fs.

I then tried sizing the PC bullets to 0.356" and seating the bullets longer.
https://images3.imgbox.com/62/ff/GVP9Wr5g_o.jpg

The middle 2 seating depths tended to give a good balance of fit and case capacity to help keep pressures reasonable. The taper crimp is not too severe although the lighting makes it look worse than it really is.

The only noticeable fouling I saw after 250-350 rounds was soot trails in the grooves of the barrels

https://images3.imgbox.com/63/e2/3KQYQPeE_o.jpg

This mostly cleaned up by pushing a dry piece of wadded up paper towel through the barrel

https://images3.imgbox.com/ed/b3/IH7lUQcO_o.jpg

A wet patch of CLP cleaned the rest out just fine

https://images3.imgbox.com/94/62/julZNukN_o.jpg

Bottom line: You shouldn't be getting lead gas cutting with PC bullets ever. Maybe PC gas cutting with under sized bullets, but that would leave soot, it shouldn't leave lead maybe unless the bullets are also skidding on the lands and exposing bare lead which is also getting cut.

If shooting in one gun, make the bullets as fat as possible but be sure they feed and chamber properly. A Lee 38 S&W expander plug acts as a poor man's "M" die. If shooting in multiple guns, you'll have to make them as fat as the narrowest gun you have and hope for the best. You may need to load differently for guns with too much diameter differences.

Use a taper crimp die in the final step rather than the FCD only to close the flare just beyond vertical. 9mm would be the only caliber I would not use the FCD. I do use it with PC'ed 45, 38, 357 and 40 although I could probably live without it.

Thanks for an informative post.

I haven't found my throat or chamber to be especially tight in my M&P, and since it's the only 9mm I load for right now, I'm just sizing all my bullets to .358".

Now that I have WEET'd my mold, it's dropping right where I want it and I can easily get super consistent .358" bullets after PCing and push-through sizing.

The problem was that my cases were swaging the bullets down. I replaced the stock expander plug with the 38 S&W plug from Lee ($6), and the issue went away. I still haven't been able to get the ring out of my FCD, so for now I just omitted the crimp step entirely. Think I dialed in just the right amount of expansion because I'm having no trouble seating without swaging, and my rounds are chambering 100% without any hangups. The bullets are also under enough neck tension not to budge when I push on them.

Took 90 rounds to the range today and came home with zero leading. A dry patch through the bore on a jag returned the barrel to shiny like-new condition. Woohoo!