Lee M Series Dies for 9mm

[Ruger 15151]

I use Lyman resizing dies when I am loading 9mm. Because Lee sizing dies size the cases down to .371 and I primarily use .3555 plated bullets, I had a problem with hour glass shaped reloads and the bulge was not always even around the case. This occurs even when I have about a .002 flar and am careful to seat the bullet flat. I always use a Lee FCD so all my loads cycle fine.

The Lyman M Series Expander Die seems to have been the solution, The first step expands the case and a second step creates a step for the bullet to sit on. Now I only get a slight bulge every 20 cases so I am very happy with these expanders.

However, I know neck tension is extremely important to accuracy in 9mm. The second step creates a shelf down about a 1/16 of an inch. Even though I use a Lee taper FCD to crimp a .3555 diameter platted bullet to .376-.377

I am curious if anyone has experience with the Lyman M Series Expander Die. Have you noticed any additional powder burn along the case or expienced any negative effect on accuracy.

EDIT - I am referring to the Lyman M-Series Expander dies. Thanks for the correction.

 

[9mmepiphany]

I've never heard of this, is it something newly introduced?

The closest die to your description is the Lyman "M" die

 

[LiveLife]

I am not aware of Lee Precision making "M" type die. Only stepped powder thru expander I know are made by NOE for 38 Spl/41AP but not for 9mm - http://noebulletmolds.com/NV/index.php?cPath=91

I was tilting 115 gr Winchester FMJ bullets that has sharp bullet base which produced pronounced bulge on one side of case from insufficient flaring of case mouth but careful seating of bullet with sufficient flaring resolved that issue with slightly even bulge around the case neck which is normal. 9mm is a tapered case and I do not mind the "Coke" bottle look as it indicates good neck tension. BTW, I do not use FCD.

One sided bulge from tilted sharp FMJ base

Slightly even bulge around the case neck showing good neck tension

 

[kingmt]

I'm a little confused also. I wanted to point out that neck tension isn't as much for accuracy as it is to stop bullet set back that will blow up your gun.

You can't add this tension after the bullet is in the case. The I'd of the case need to be about .002" smaller then the bullet bring seated. I've never use a FCD but it sound hard to mess up but if you over crimp or size the upper part of the case with the bullet in it then your going to lose neck tension.

 

[Ruger 15151]

I am not aware of Lee Precision making "M" type die. Only stepped powder thru expander I know are made by NOE for 38 Spl/41AP but not for 9mm - http://noebulletmolds.com/NV/index.php?cPath=91

Thanks bds.

I am familiar with the NOE stuff. I spoke to NOE about purchasing the stepped expander plugs for my Lee powder thru dies. However, they are are now only making the stepped expander for standard Lee expander dies. I believe standard stepped expander dies are available from Redding and Lyman. Dillon also offers a powder thru version.

I assume you are seating the bullet and removing the flare in the same step. Do you feel that the FCD over crimps or just don't see the need in this extra step?

 

[LiveLife]

I assume you are seating the bullet and removing the flare in the same step. Do you feel that the FCD over crimps or just don't see the need in this extra step?

I was taught to reload on Dillon 550 and Lee Pro 1000 to make USPSA match loads by a bullseye match shooter. When I asked him about the FCD, he showed me a drawer with FCDs and said not necessary.

Since I add .022" to the diameter of the bullet which is hardly any taper crimp, amount of inward movement of case wall as the bullet is seated is very slight, even when using lead/coated bullets to not shave the bullet.

In addition, many barrels are oversized at .356"+ and if I am using larger than .355" sized bullets, I do not want to post size the bullet to reduce bullet diameter which would decrease bullet to barrel fit and neck tension from brass spring back. With .355" sized bullets which the FCD was intended for, I do not see problem using the FCD.

If you were using a lot of crimp, separate seating and crimping operation would be better, especially with lead/coated bullets to not shave the side of the bullet.

 

[Ruger 15151]

Here are some of the 9mm loaded using the Lyman M-Series expander and step/flair removed with the FCD. Finished diameter is .377.

 

[LiveLife]

Looking good.

Best way to measure post sizing, if any, is to measure the bullet diameter before/after FCD.

If no reduction, you are good to go.

 

[Ruger 15151]

Thanks. I'll make a few dummy loads then pull the bullets to check for any changes in diameter. Are those Winchester FMJs?

BTW... I take it that those cases were tumbled in corn cob media and NuFinish? OCD..cant help it!

 

[slickracer]

Get yourself a .38 S&W expander from Lee (not .38 Special). It's a well known trick for cast bullets and may solve your problem.

 

[LiveLife]

Are those Winchester FMJs?

BTW... I take it that those cases were tumbled in corn cob media and NuFinish? OCD..cant help it!

Yes, Winchester 115 gr FMJ.

OCD? Sure!

Brass was tumbled in fine grit (24) Harbor Freight walnut media with NuFinish polish in Berry's tumbler loaded with about 800 cases (capacity max is 1000) and buffed with cloth towel.

 

[Ruger 15151]

Awesome... Thanks!

BTW- Do you tumble your finished cartridges after reloading?

 

[Schwing]

Back when I still reloaded 9mm using a lot of lead bullets, I used the M-die. It fixes a couple of issues with lead bullets. The first is, as you said, it doesn't swage the bullet down which kills accuracy. The second is that the M shape created in the case pretty much prevents any setback even if you get poor neck tension.

"Get yourself a .38 S&W expander from Lee (not .38 Special). It's a well known trick for cast bullets and may solve your problem."

This was the best solution until the bullets start getting larger in diameter than about .357. I have a couple of 9mms with barrels that are .358 so I have to size my bullets to .359 to get any kind of accuracy out of them. For those, the M-die is still the best solution that I have found.

edit:

I would recommend testing your rounds without using the FCD. I used to be a big believer in those but have found that they do very little to increase reliability and they are usually not good for accuracy. If your round cycle fine without being run through the FCD, I wouldn't use it. Even if they don't cycle well, I would figure out where that problem is and fix that vs. using the FCD.

 

[Ruger 15151]

Thanks Schwing.

How are you removing your flare... with the seating die??