Question about 9m/m cases?

[Ala Dan]

First, let me state that I had NO idea of the amount
of different headstamps in the 9m/m caliber. Sorting
through a quanity of mixed 9m/m range brass, this
quickly got my attention! Win, R-P, FC, Federal, IMI,
Geeco*, and the list goes on and on. Anyway, I am
getting ready to load a batch of 9's; and I read that
there is a wide variation regarding case length, even
amongest the same manufactuer? In this case, the
writer said his 9m/m firearm prefered both, Win and R-P
cases that measured .750 in length. He went on to
say, that he settled on an OAL of 1.130.

Here's where the kicker comes in! He stated that with
the 9m/m, a cartridge that has an operating pressure
in the 20-25, 000 range; given a small increase in the
seating depth (he used .030") would increase the CUP's
to up over 60,000, and would ultimately destroy your
weapon. My question is, is this information correct?
I realize that in most instances the 9m/m is loaded
as a "compressed load"; but I never thought about how
dangerous the 9m/m could actually be.

The article went on to say, that his 9m/m (unknown
make or model) functioned best with Hercules Unique;
or what is known today as Alliant Unique. He stated
that he achieved greater accuracy from the flake type
powder.

*FootNote- "Geeco" what outfit produces this ammunition?
Reminds me too much of Geico Insurance!

Best Wishes,
Ala Dan, N.R.A. Life Member

 

[stans]

9mm is a high pressure cartridge for sure! Seating bullets deeper, whether intentional or as a result of bullet set back does increase pressure. If your load is near or at maximum pressure, then bullet set back or a deeply seated bullet can cause some serious problems. Fortunately, most 9mm's sport fully supported chambers, so most reloaders see primers that are totally flat and flowing into the firing pin hole and a bulged case and usually no more than this. If you have a 9mm based on a 1911, the story might be different.

Be careful when working up to maximum loads in 9mm. Really fast powders such as Bullseye and W-231 are fine for loads that will just barely make factory velocity (1150 to 1200 fps with a 115 grain bullet). Unique and AA#5 can be pushed a little further. Blue Dot, and I have no experience with this powder, supposedly allows the highest attainable velocity in 9mm.

I have loaded 9mm for many years and found 115 grain JHP's (Remington) over 4.9 grains of W-231 to be pretty accurate in my 9mm's. I load this to an OAL of 1.115", so this is a little on the long side, but functions well in my 9mm's. I have chronographed this load at 1179 fps in my S&W model 439 and 1185 fps in my TZ-75. I used Midway brand cases and Winchester small pistol primers.

Disclaimer: This is not a starting load! Back off the charge and work up. This load is safe in my guns, absolutely no guarantee it will be safe in any other gun. Use this load at your own risk.

 

[wanderinwalker]

Ala Dan,

First, that GECO brass is good stuff. My uncle shot up a whole bunch a couple of years ago in one of his SMGs and I'm still loading the stuff.

Second, W-231 powder will work for the 9mm. I have better luck running the stuff under a 124gr FMJ than with the 115s. It's difficult to get this powder to function some firearms reliably with less than max-published loads. (I admit, I load 115gr Rainiers with W-231 and my charge is just over the book max.) Another powder I have had good results with is W-Super Field. Cleaner and more potent than W-231. Of course I'd also have to suggest Alliant Power Pistol! This is awesome stuff! Flash, blast and OMG ballistics. I once chrony'ed a batch of PP at 1175 fps with a 124 out of a 3.5" barrel!

As far as cases go: If you're loading bullseye ammo, go ahead and sort 'em. I don't shoot bullseye, so my 9mm loads are whatever brass is clean goes into the press to make live rounds. FC, FC NT, Win, R-P, Speer, Geco, reclaimed NATO, Olympic, S&B, et. al. Work fine.

Lastly, don't worry excessively about the pressure issue. As long as you keep your OAL around 1.15" (+/- a little, I load to 1.16" because my Glock shoots better with the slightly longer rounds) you'll be fine. The 9mm runs at about 35k PSI in SAAMI trim, more in CIP, NATO and +P/+P+ guise. I haven't encountered any problems with pressure levels in MY pistols, but just keep your eyes open. Not knowing what you are loading for, I suspect you may have problems getting the pistol to cycle with starting loads and possibly even with max loads with some powders and bullet weights.

There, hope it helps a little,
~Nate

Edited: Alliant Power Pistol is reputedly the powder used to load US Mil-Spec 9mm ammunition.

 

[Ala Dan]

Great responses guy's, I appreciate it immensely. Maybe
I thought you all knew, but I definitely forgot to mention
that I'm loading for a West German (early production)
SIG-SAUER P228.

My choice of LEAD bullets, are the Magnus 122 grain
SWC's. In case you are unfamiliar with these, they have
what I call a short neck. Before I read this article, I have
successfully loaded and shot this round through this fine
firearm. Looking back at my handloading notes, I loaded
this bullet into a batch of mixed headstamp cases; under
3.5 grains of Alliant Bullseye. On that date, this loaded
was tested in SIG-SAUER's P226 and P228, and also a
Browning Hi-Power "Practical" model was used.

Dang it! I forgot to record the OAL :banghead:

Again, thanks for the expertise help my friend's!

Best Wishes,
Ala Dan, N.R.A. Life Member

 

[Mikul]

I played with overall lengths(OALs) with my 9mm. My usual load has a 1.120 OAL. I saw no difference until I reached 1.113 when the velocity went up a consistant 15fps. By the time I tested a 1.090 it was up 120fps which is a whopping big deal. There's a certain point where the pressure seems to go critical and that will be different for every bullet, case, and powder combination. Work up your loads in small increments: no more than 0.2gr at a time.

The 9mm runs around 37,500psi. That's high pressure for a pistol round.

Geco is high quality, German-manufactured ammunition. I was able to find it cheap at a local gunshow (about $100/1000), but I don't see it anymore. S&B (Sellier & Bellot) is also good, Czech-manufactured ammo, but the primer pockets can be tight.

 

[Ala Dan]

Yep, I've run into some S&B 9m/m's with tight primer
pocket's, when loading a previous batch of ammo. I
just finished full length resizing the R-P cases; and
also the box full of mixed headstamps. Think I will
save the R-P's and Win's to use as dedicated bulls
eye cases; and load and shoot the mixed headstamps
for practice. Most likely will work up a load using
Alliant Bullseye powder?

Best Wishes,
Ala Dan, N.R.A. Life Member

 

[Navy joe]

*FootNote- "Geeco" what outfit produces this ammunition?

Geco is made by Dynamit-Nobel. The factory ammo is what I would buy if I didn't reload. Very consistent.

My thoughts. .030" in seating depth is huge, not little so you better adjust your powder charge. I use a real mix of brass for 115 loads in the 1130-1170 FPS range, nary a problem. The brass really affects accuracy though, consistent case volume and expansion in the chamber varies wildy. I prove this by sorting loaded rounds by headstamp and shooting groups. My favorite brass is WCC, it weighs about 2gr more than other cases and the wall thickens halfway down. Very consistent, you just deal with the crimped primer.

 

[Ala Dan]

Thanks for the info thus far folk's. Navy joe, keep in
mind that wasn't me adjusting the seating depth by .030";
it was an un-named author who wrote the article I was
reading. He tested a variety of 9m/m loads; giving all the
details except what weapon he used? I would say from
the looks of his notes that this was an avid "unclassified
internet author"; as this was five pages of notes that
someone had copied from his website.

Best Wishes,
Ala Dan, N.R.A. Life Member

 

[caz223]

Most big name 9mm brass is way stronger than it needs to be.
For instance, starline's 9mm and 9mm +p brass differs in headstamp only.
Same brass, different headstamp. (I'd assume for load identification.)
As for 9mm pressure levels, that's why I use powders that fill the case to the base of the bullet (No possiblilty of a double charge.).
Also, I tend to use powders near the slower burning side of the range for the application.

 

[Clark]

CAUTION: The following post includes loading data beyond currently published maximums for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The High Road, nor the staff of THR assume any liability for any damage or injury resulting from use of this information.


If ones overloads the 9mm until the case bulges in the image of the feed ramp, and then varies the seating depth to map the threshold of case bulges [or pierced primers or primers falling out] as a function of seating depth, one will find:

1) Only a few powders have the speed - density product to GET a case bulge in 9mm.
2) Decreasing the OAL makes even less room for powder and reduces the small group of powders that can get a case bulge in 9mm.
3) The effort of trying to get that much powder to fit in the case can bulge the bullet or bulge the case on seating causing a pinched bullet causing a pressure spike. The pressure indicator may erroneously be then attributed to seating depth. Pre compressing the powder and resizing the loaded ammo will prevent the false pressure indicator.

--
A society that teaches evolution as fact will breed a generation of atheists that will destroy the society. It is Darwinian.

 

[BluesBear]

The Alliant Powder Reloaders Guide shows 9mm loads in the 30,00psi range.

As for S&B ammo, just use a primer pocket tool like you use for removing the primer crimp on military brass. Your S&B will then load much easier.

I usually do it on all foreign cases just to keep everything consistant.