first posting.

[hammered54]

hello all,
been lurking for over a year now on and off..good stuff here.
starting to reload and have a few questions.
I have older but never used RCBS equipment ( late 70's early 80's) that I'll be using.
as of now I'm set to reload 44mag. and 9mm luger, later to add 30.06 ,40 S&W 45acp. and 8mm mauser.
now ..I'm checking case sizes for the 9mm, book says .754 after sizing, but nothing checks any longer than .751, 752 and some as small as .749.
is this going to be a problem?
I've made a few dummie rounds to check fit in my S&W Mod 39-2 and they seem to fit just fine.
is the .754 a Max. lenght how much shorter can I get away with?

this is once fired prossessed brass from TJCONEVENA.

thank's Matt.

[Pahoo]

Welcome aboard and are you really "Hammered" ....


Be Safe !!!

[Krieger9]

Grew up there. Living Just north now.
Belong to the Howell Gun Club, ever shoot there?

[hammered54]

ha..hammered no ..it's a long story that go's back 30 years...we'll get to that another time.
somehow hit reply before I was done typing..duh.

[Doodlebugger45]

Interesting. Usually people have the opposite problem in that their used brass seems to be too long. I know nothing about 9mm or any other autos other than it is supposed to space on the mouth of the case. About the only thing I can suggest is to go ahead and load up maybe 5 of the shortest ones. Make sure the OAL is within limits. Then see if they actually cycle in your pistol. Make sure you're not making a hot load of course. But if your pistol cycles with them, it shouldn't be an issue.

By the way, I think you are starting out the right way. 44 mag is simple to load for and very forgiving. And the 9 mm is a lower pressure round than the .40, so that will give you some experience with the easier auto round. After you feel good with them, you can go to the other pistol cartridges. When you really think you are mastering reloading, then you finally want to tackle bottleneck rifles. Then you will feel humbled at first because there are more variables to consider with rifle cartridges.

[g.willikers]

Ahem,
Hate to interrupt this gabfest, but maybe we should try to answer the gentleman's question.

The variance in the case lengths, after resizing, might be due to the differences in manufacturing, by the various case makers.
There can be differences in case wall thickness, and sometimes even a little in overall length.
As long as the finished cases are within industry specs, they will wind up as ammo.
Which is why cases are sorted by mfg and spec for reloading.
Rifles more than pistols, but both as this can greatly increase the results and accuracy of the finished loads.
The internal volume of cases, under the bullet, has a definite effect on the internal pressures, so overall length of cases is important.
The shorter the case, the less powder is needed to produce a given velocity and pressure.
Bullet seating depth will also have effect on velocity and pressures.
And this will vary when determining the overall length of the loaded round, if the cases are not all the same length.
If your cases vary a lot, you should get a chronograph to see what's what.
Then you can decide if the case length differences are really a problem.

[rg1]

You'll find 9MM brass will vary in length even from the same batch and same brand of case. It's most common for them to range in length from .745" to
.750". Occasionally I'll find one a little shorter than .745". Seldom do I find once fired 9MM that's .754" and even though I check every case I've never seen one longer than maximum length. Haven't had any failures with brass approx. .010" shorter than max. Not necessary to trim to a uniform length and your taper crimp die will work fine getting a good taper crimp with the variance of case lengths. I've read where some say 9MM cases and some other straight wall cases actually get a little shorter with repeated loading and firing? I've only been loading 9MM for about 5 years now and probably around 5000 rounds loaded.

[hammered54]

great info guys,
it seems as most of the brass is WIN. F.C. and a few Blazers.
after rechecking set up of the dies it turns out most is falling in the .753 range
(sized 80 so far) of the 80 a few (3 or 4) have been .749.

now , I've reloaded about 10 round's with berrys 115G RN plated with 4.8G of bullseye to a OAL of 1.100 , loaded the mag. and went out back and........all seems good, bullets fired well, chambered well,ejected well...so did I miss anything ?
I'm a think'n I can get into this.
thanks Matt.

[g.willikers]

My loading data says that your loads are just under the max for powder and just under min for oal.
Max is 5 grains of Bullseye and min oal is 1.12.
The slightly less than max of powder might compensate for the slightly too deeply seated bullet.
But, with the relatively high pressures of the 9mm, maybe seating the bullets out a little would be a good idea.
Unless, of course, your data says different.
Either way, just keep an eye out for high pressure signs.
If none show, then don't sweat it.
To add to the confusion, the oal might be determined by what feeds in your particular gun, and everything else is relative to that.

How accurate is the 115 grain RN?
Some 9mms are more accurate with longer bullets that engage the rifling better.
Others not.

[TXGunNut]

Welcome to the asylum, hammered54. Haven't loaded 9mm in awhile so will defer to the good advice above.

[Lost Sheep]

Welcome to the forum (or, perhaps, I should say, welcome to posting.) And thanks for asking our advice.

Originally Posted by g.willikers

Ahem,
Hate to interrupt this gabfest, but maybe we should try to answer the gentleman's question.

Yes, indeed. The implied questions (to my mind) is if an extra .03" headspace might be a problem.

First off, the volume inside the case under the bullet depends on the overall length of the cartridge (and the length of the bullet) and is completely independent of the length of the case body. Lop ten thousandths off of a case and seat the same bullet to the same overall length and the volume inside the case remains exactly the same.

The main problem with short cases is that the base of the case may not be close enough to the breechface for 1) good ignition and 2) good pressure containment. The case is (intended to be) held tight against the breechface by the case mouth hitting the "step" in the chamber that is (by SAAMI standards) set such that a cartridge case .754" long will be held properly, thus define the verb "to headspace".

Forgive me if I have repeated stuff you already know. I do not know your level of expertise, and others of all experience and knowledge levels are reading.

The problem with short cases and headspace is sometimes alleviated by the fact the case is often held against the breechface by the extractor. This allows people to shoot (foolishly) .380 Auto (9x17) and 9mm Makarov (9x18) in 9mm Parabellum (9x19) chambers. It is not a good idea, but the guns chambered for 9x19 will semi-reliably go "bang" with 9x17 and 9x18 cartridges if they have good extractors. But I digress.

If the extractor holds the case against the breechface, you are sort of OK. If the case falls more deeply into the chamber (because the case length is so short that the case mouth does not hold the base against the breechface) a bad thing may happen (if and) when the primer ignites.

1) The primer ignites the powder, the case walls expand, sealing against and gripping the chamber walls and the base of the cartridge moves back against the breech face. If the case walls stay stationary against the chamber walls, the case walls stretch at a point just in front of the web, getting thin there. If the brass in that area gets stretched thin enough it may result in case head separation and the escape of high pressure gasses. Down the magazine well, possibly out the grip panels into your hands or through the slide and into your face.

I don't actually know the point at which short length becomes dangerous, but you can get an idea if your case walls are getting thin by the "paper clip test". Straighten a paper clip and then put right-angel bend in the very end. Stick this end in a fired casing and try to feel for a ring inside the case where the case wall thickness is getting thin. If you find such case, it is a candidate for discard. I would guess the length (at this time) would be proper (having been stretched out to the proper dimension upon the most recent firing). But its length before firing would be the shortest length I would ever fire in that gun.

I hope a more knowledgeable forum member will weigh in with better statistics and a better explanation with better writing style.

Unclenick?, are you out there?

I hope that what I have written is descriptive enough to illustrate the important factors.

Doodlebugger45, I think a slightly short case will cycle through the action just fine (as long as the overall length is not too LONG, which is not likely, considering the case is shorter than SAAMI spec). A short overall length should have no problem cycling. It is what happens upon FIRING that has me concerned.

Lost Sheep

[engineermike]

Hornady calls for a C.O.L. of 1.100 and a range of 3.9 gr, 4.2 gr, 4.4 gr, and a max of 4.6 grains of Bullseye and velocities of 1000 (3.9), 1050 (4.2), 1100 (4.4), and 1150 (4.4). This is for their 115 gr FMJ round nosed bullet. They show a max C.O.L. of 1.169, and a max case length of .754, and case trim length of .749. (I have not had to trim any of my cases so far) You may find that Berry's bullet are somewhere between cast lead bullets and the Full Metal Jacket (FMJ) when picking an amount of powder for these bullets. I use the Berry's bullets in my S&W 40 and 38 special loads. As for the 9mm I sold that gun and have not yet replaced it, but I am looking for another 9mm.

I don't load with Bullseye but I find my Ruger 9mm is most accurate at a C.O.L. between a C.O.L. of 1.125 and 1.130. using Win 231 powder (4.4 gr.) so you may want to load a few at various lengths (between 1.100 and 1.169 and see which one/ones your gun likes.

Mike

[hammered54]

I'm reading it all guy's and getting a better understanding of the relationship between ..case length, OAL, ect.

this is new to me, taking my time and soaking it all in.
thanks Matt.