9mm leading solved

[bdixon]

There are a lot of 9mm leading threads on this site, so I am posting this to hopefully help some people. I know my experience isn't the answer for everybody, but it may help some.

I started casting about a year ago and started with 9mm. Over the last year, I have tried at least 6 different bullet designs, 3 different powders, and 4 different lubes. I slugged my barrel at .3563" and tried sizing my bullets to .357, .358, and .359. I tried air cooling my boolits and water dropping. I found that if I water dropped, they were hard enough to not be sized down when I would seat the bullet into the brass, at least that's what my digital caliper told me. No matter what combination I used, I would get leading in the last 1"-1.5" of my barrel.

I read a thread here where somebody suggested using a Lyman M die, so I ordered one and gave it a try. Problem solved. The M die fixed everything. I shot around 150 rounds with very little leading. I don't know if I really understand why the M die fixed my problem, but it did. Before using the M die, my boolits weren't being sized down when seated in the brass enough, if any, to cause any problems. I'm sure it has something to do with the tension of the brass on the bullet, but what do I know?

Anyway, I hope this helps somebody. I was sure excited when I looked down my barrel and it was clean!

[Pirate69]

Can you share your load and which pistol you are using?

[plus1hdcp]

Good to hear! I will add to Pirates request you to share the data.

[bdixon]

I'm shooting a Sig P239.

Today I shot the Lee 356-125-2R Round nose bullet and the Lee 358-125-RF with 4 grains of Unique. There was a combination of water dropped and air cooled bullets and they all worked fine.

I also shot a 147 grain bullet with around 3.2 grains of Unique (I'll have to double check that).

[Mikael]

The M die get alot of praise and no smoke without fire, I'm sure it's all that and then some :)
BUT, as I've understood it, it's not a powder through die?

Oh, and I'm glad for you, congrats on solving the problem :)

[NHlever]

Since the "M" die creates a step, I wonder if it has something to do with getting the boolit started straight when it is seated. I know that I have sometimes had problems with that when using dies that only flare the case.

[9.3X62AL]

Mikael--

The Lyman M-die comes in both forms I believe, the hollowed-out spuds being adapted to a powder-through-expander setup that Lyman calls a "Multi-Expander Die Set". I am a HUGE fan of the M-die for case mouth prep for cast boolit seating.

[soldierbilly1]

Bdixon:
Eventually, what alloy and lube finally worked? What size worked, or, did they all work with the Mdie?
Just curious, I have experienced similar problems with my XD9.
thanks
Billy boy

[Mikael]

Mikael--

The Lyman M-die comes in both forms I believe, the hollowed-out spuds being adapted to a powder-through-expander setup that Lyman calls a "Multi-Expander Die Set". I am a HUGE fan of the M-die for case mouth prep for cast boolit seating.

Thank you! :)
I'd have to check up on that. Not that I have noticed any swaging of the boolit when seating, but might be worth it anyhow :)

[reloader28]

We had that problem in my brothers 9mm and I bought one of Pat Marlins plain base gas check makers. Fixed my problem right up. Better accuracy and zero lead in the barrel.

The only down side is I have to drink a beer now and then to get the checks. I get 85 checks from one pepsi/beer can.

[bdixon]

Bdixon:
Eventually, what alloy and lube finally worked? What size worked, or, did they all work with the Mdie?
Just curious, I have experienced similar problems with my XD9.
thanks
Billy boy

Both air cooled and water dropped wheel weights worked fine. I have been using Carnauba Red and also some Felix Lube. So far I have tried unique and blue dot, both worked fine. I think the M die fixed all of the problems, no matter the combination.

[RobS]

Your boolit's base may have seemed un-sized however it may have been possible that the very edge of the base could have been swag down allowing for gas cutting. The Lyman M-die just may have fixed this as it expanded the case.

Also there is the possibility that with the M-die the case mouth is expanded so has less neck tension. Less tension may have the round starting with lower pressures.

[243winxb]

bdixon, were you using this Lee tool to open the case mouth, before you bought the Lyman "M" die? This Lee die does not expand the inside of the brass correctly. http://www.thegunsource.com/DisplayPic.aspx?PIC=34410

[Doby45]

I use custom made expander plugs that do the samething as the "M" die and let me tell you they are a LIFE saver. Mine are also powder through. ;) Gear knows what I am tawkin about..

[bdixon]

bdixon, were you using this Lee tool to open the case mouth, before you bought the Lyman "M" die? This Lee die does not expand the inside of the brass correctly. http://www.thegunsource.com/DisplayPic.aspx?PIC=34410

Nope, I was using the RCBS die that came in the 3 die set for 9mm. That only flared the mouth a little, it didn't expand the inside.

[Iron Mike Golf]

Mikael--

The Lyman M-die comes in both forms I believe, the hollowed-out spuds being adapted to a powder-through-expander setup that Lyman calls a "Multi-Expander Die Set". I am a HUGE fan of the M-die for case mouth prep for cast boolit seating.

Yep, that's what I use. You get a set of hollow spuds in various calibers. You also get adapters to mount a Lyman #55 on it. I just use it as a funnel.

If you get one of these and use it for charging, I recommend sanding and polishing the interior funnel slope. It's kinda rough and sometimes powder kernel can stick. I wet sanded with 400 grit sandpaper follwed by Flitz. Nothing sticks any more.