Spinning Bullet in Brass Case?

J

jetblueshooter

Inactive
I am new to reloading with a Hornday 5 stage press, and I'm currently trying to get my 9mm Luger setup correct. I understand the 9mm Luger is a tapered brass case at the top. Currently as follows;

1. Decapping die (RCBS)
2. Expander die (Redding Premium, replaced RCBS one)
3. Powder Drop (Hornady)
4. Bullet seater die (RCBS)
5. Taper crimp die (only) (Hornady)

Everything seems to flow well now except for one problem. After completing stage 5, the Taper crimp die, the bullet spins in the brass case. Here's how I ended up there;

- I started with a crimp that seemed right, but the bullet would still slide into the brass case after crimping it. So, I slowly tightened the taper crimp die to the point where it definitely will not slide into the case, but now just spins.

- Next, I tried just applying more crimp to see if that would help, but it did not help. I started looking at the case, and I can actually tell where the crimp die stops. The last time I tried I could tell the crimp die was stopping about 1/8" below the case mouth.

Maybe there is something really obvious I'm missing here. I'm sure nobody is putting adhesive on the the bullet :)

Thanks for the help, very much appreciated!
 
The taper crimp isn't really intended to "crimp" -- its job is to remove the flare from the case mouth. With semi-auto handgun cartridges, the primary mechanism for bullet retention is supposed to be the friction between the bullet and the case wall.

It sounds to me like your expander is expanding the cases too much, or the bullets you are loading are undersized.
 
Here the bullets I am using, are these undersized?

SPEER 9MM 115 GR
.355" CRPN
Copper-Plated Round Nose
No Exposed Lead

If these are not undersized, then I can tweak down my expander more (so if the bullet is .355"... flare should be...?)

Thanks Aguila.
 
One operation I did not see in your progression is resizing. ?

A typical 3 die set would be a resizing die,a decap/bell die, and a seater die.

The inteference for neck tension is provided by the resizing die.It sizes the case down.
Now,the expander plug/bell/(and often decap )spindle would typically be the final operation to uniform the neck tension. You may have a powder drop though the expander. You DO have a "put together" set of dies. Thats fine,but I can't know exactly what you have.The 9mm at .355 is a little smaller than he .357/.358 expander for the revolver cartridges. If a 357/358 expander was substituted into your setup,thats something sneaky that could mess you up.It could happen at RCBS or Redding. Of course,to provide tension,the actual expander plug must be undersize.I will guess about .003. So your 9mm expander should be about .352
If you are dropping powder through a spindle that enters your cartridge case,check that,too.

On your crimp die: Revolvers and semiautos have different needs from a crimp.

In a revolver,cylinder freebore,gap,and forcing cone do not provide the resistance required for good ignition. The roll crimp resists the bullet ,maintains the powder "boiler room" so heat and pressure can rise..
The revolver crimp also resists recoil bullet pull. The crimp is designed to resist the bullet moving OUTWARD.
In semi-autos,the crimp is designed to resist the bullet being forced INWARD,deeper into the case. The forces involved come from magazine feeding. The dangers are stoppage,and increased pressure from reduced combustion chamber volume.

Typically,these cartridges headspace on the case mouth,so the crimp must be limited.Yet still,some crimp beyond just ironing out the bell is preferred.

Some of the reloading manuals give a crimp diameter dimension.

Simply set your crimp die to that diameter at the case mouth

It is true that too much crimp can expand the case walls outward ,reducing neck tension.

Try .377 to .378 for 9mm,but plunk test.
 
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Okay well here's what I have

3-DIE CARB TC SET 9MM LUGER
https://www.rcbs.com/reloading-dies...group-b---popular-pistol-cartridges/1831.html

Description
"RCBS pioneered and developed 3-Die Sets for straight-wall rifle and pistol cases. The Carbide Sizer Die sizes the case and de-primes (the carbide sizer ring eliminates the need to lubricate). The Expander Die expands the case to the proper diameter to accept the bullet, and it imparts case mouth flare/bell for bullet feeding. The Seater Die seats the bullet and taper crimps. "

Note (I threw out the RCBS expander and replaced it with the Redding below)

So, the flow goes like this:
1- RCBS carbide sizer die and de-primer (I did not know this description)
2- Redding Expander Premium Die (does the flare)
3- Powder drop
4- RCBS seater die (seats the bullet and taper crimps)
5- Hornady taper crimp die (hollow in the middle)

So, now I'm wondering. Hmm. To test all of this I've been skipping die #1, leaving in the old primer, then... expanding, seating and crimping the bullet. Is it possible that by me skipping that portion during setup it did not come out right? I did not want to waste new primers, heck I think I've blown through 50-100 cases just trying to get this working.
 
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Yeah,that skipping die #1 thing might be your problem!! :D

And as you set them up,reading the instructions might add some depth to your program!!

Glad I could help!!

You can run that brass through again.Oh,and that likely will solve the problem in the other post about fitting the gauge
 
JB,

Is your brass R-P by any chance? I don't know about the 9 mmm but Remington brass is famously thin in the necks and can quickly work-harden to the point it is too springy to resize enough to hang onto a bullet. The cure I found was a Dillon resizing die, which is tighter, almost like a small base die.

I have also run into issues with die tolerances at times. Not common, but it happens. If you have the same problem with a variety of 9 mm headstamps, call RCBS. They will put it right. They may ask you to make some measurements, though:

I note you are using Speer plated bullets. Speer likes to coat some of their plated bullets in hex-form boron nitride which is a sort of super graphite with even lower coefficient of friction than moly. That could be making it hard for the brass to hang onto them. Call Speer and see if this is a common complaint and if so, what do they recommend.
 
Thanks guys - Let me try this again when I get back to the press tonight.

Unclenick -good point I did think they were "slippery"... maybe there is a trick to make them a little more stick or score them or something. Also, mixed brass and I DID SEE some of the R-P in there.

Can you point me to this Dillon die you are talking about?

Thanks
 
This is a good outfit:
https://www.dillonprecision.com/

Its always a good idea to listen to Unclenick.

But,account of you were skipping the step of resizing,I suggest you give your RCBS Carbide sizing die a chance before you spend more money. It just might work!
 
Unclenick: I think our OP discovered a critical piece of the puzzle a few posts back.
So, now I'm wondering. Hmm. To test all of this I've been skipping die #1, leaving in the old primer, then... expanding, seating and crimping the bullet. Is it possible that by me skipping that portion during setup it did not come out right?
Click to expand...

The way I read that,those RCBS carbide sizing dies don't get a chance to do their job if you skip them.

I think he's fixing to try actually running them through the sizing die first.
 
jetblueshooter said:
If these are not undersized, then I can tweak down my expander more (so if the bullet is .355"... flare should be...?)
Click to expand...
I see from a post after the above was entered that you have been skipping the resizing step. That's probably why your bullets are spinning after seating and crimping. Nonetheless, I'll throw this out there for additional clarification:

Note that your #2 die is called an "expander" die, not a "flaring" die. Yes, it also adds the flare, but it has a stem that goes into the mouth of the case and expands the case to a depth that approximates the usual seating depth for the bullets. But the expanded case mouth should still be smaller in inside diameter than your bullets are in outside diameter, so when you seat the bullets you are forcing the bullets to compress slightly while the case stretches slightly. This is what holds the bullets in place until the powder goes off.

The flare (or "bell") is there only to provide a stable platform for the base of the bullet to sit on as the base and bullet are fed up into the seating die. Too little (or no) flare is what results in bullets tipping on the case and seating crooked -- which you previously encountered, when we recommended increasing the flare slightly. Then, for semi-autos such as 9mm, the taper crimp die isn't really crimping the case mouth, it's only removing the flare so the cartridge can chamber fully.

The stem on your expander die should be something like this:

| |
| |
\ /
||

Can you point me to this Dillon die you are talking about?
Click to expand...
You don't need it. You already have a perfectly good resizing die that you haven't been using. If you had used the resizing die, you wouldn't have needed to replace the expander die. If you didn't resize the brass, the reality is that neither of your expander dies did any expanding, because the brass is probably already larger than they expand to.
 
HiBC,

From JB's statement that he is "leaving the primer in", I assumed the case was previously resized and primed and that he is re-working it only with the expanding die to reopen the crimp. Of course, that would be futile for getting a tighter crimp, as the expander is only for expanding a case back out after the sizing die has over-resized it (standard practice to compensate for thin brass). He would need to unscrew the decapping stem from his sizing die and re-resize it. But I'm not sure why that would help at that point, as it should just reset the problem.

JB is correct it is possible his expander is too wide for those bullets and needs to be reduced if I am right that this problem occurred after the initial proper reloading attempt. Again, he could send sample cases, sample bullets, and the dies to RCBS and let them figure it out.
 
(Response to AB)Here is an article on setting up a die for taper crimp.

The author explains the rule of thumb math that typically works.

Measure bullet diameter. Measure case wall thickness. Add bullet diameter to 2x case wall thickness . Then subtract .004. Thats what you want to measure over your crimp at the case mouth. Its .002 per side.

I agree you need sufficient neck tension.

I disagree that the tapered crimp function of the die is only there to iron out the flare.Thats ill informed misinformation.

A .002 per side crimp helps prevent bullet setback. And you have a known,precise,repeatable measurement. Thats how you make consistent ammo

https://www.handgunsmag.com/editorial/squeeze-play-how-to-properly-crimp-ammunition/138116

(Response to UN) Fair enough! Its hard to interpret exactly what is going on.
In post #4 I suggested he measure his expander plug and any powder drop that may act as an expander. Its conceivable at RCBS or anywhere a .357 Magnum expander got dropped in a 9mm stockroom bin. It may have been assembled into his dies.
I agree,RCBS will be happy to straighten it out.
 
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Unclenick said:
From JB's statement that he is "leaving the primer in", I assumed the case was previously resized and primed and that he is re-working it only with the expanding die to reopen the crimp.
Click to expand...
I read it the way HiBC read it -- that JBS skipped the resizing step because he didn't choose to decap the cases. If that's the case (no pun intended), his expander is probably expanding air, because the fired cases are all probably larger than the expender stem's diameter. That would explain why the bullets can spin in the case after seating and crimping. That would also explain why his cases wouldn't drop into the case (or cartridge) gauge.

HiBC said:
A .002 per side crimp helps prevent bullet setback. And you have a known,precise,repeatable measurement. Thats how you make consistent ammo
Click to expand...
Bullseye shooters I know disagree. They want "neck" (case) tension to hold the bullet, and to massage the case as little as possible after seating becausee anything you do after seating may reduce neck/case tension.
 
The only reason I can think of for loading a case without decapping is if the primer is still good, and the only reason the primer would still be good is if it wasn't fired after the previous decapping and simultaneous resizing. But, clearly, JB hasn't quite got his head wrapped around the mechanics of the process yet, so perhaps he'll come back and clarify.
 
o test all of this I've been skipping die #1, leaving in the old primer, then... expanding, seating and crimping the bullet.
Click to expand...

If I'm reading this correctly, he's been TESTING his crimp settings using FIRED,. UNRESIZED brass.

Which is why his bullets are still loose (spins) in the case, even after being crimped.

Separate your brass by headstamp. Different brands (sometimes even different lots from the same brand) can have different thicknesses. Often it doesn't matter, but it can, and when it does, it definitely DOES.

Size your test cases, just like all your regular brass. leave out a new primer and powder but do all the other steps just as you would loading ammo. See what results you get, compared to what you're getting now.

And, get yourself a bullet puller. I can recommend the "orange hammer" from Lyman but the RCBS or any other quality brand should work as well. I disrecommend the press mounted collet type pullers.

At some point, you WILL want a bullet puller, possibly sooner than you think. :D
 
You may be correct. When he says he did not want to waste new primers, perhaps it is meant the way you say, and he did not mean there were new primers in the cases that he did not want to waste, which is how I took it initially. Perhaps he did not realize cases are expanded during firing to let go of the bullet and therefore fired cases would be too wide to hang onto a new one without resizing. Still, no reason not to resize and decap and just not put a new primer in if you are not going to load them anyway. Anyway, perhaps he will clarify.
 
Hey guys I am the car dealership on Wifi.. looking here before I get back to try the next thing but wanted to answer some of the questions. You guys really know this stuff.

The Primers - Yes you are right, I skipped the de-priming/resizing die because of two reasons (1) to save money on primers, and (2) I did not know that this die did any resizing. So, I think 44AMP and Unclenick you guys referred to a better idea -- I could have simply removed the depriming pin from that die and left the old primer in there until I got everything set, and then put it back in. But going forward on new setups that's a great idea.

Now, before I left the house I did 2 things that actually worked pretty good:
1) Took your advice and set the expander +.002 so I set it at .357.
2) Reset the Hornady crimper die (after bullet seat) - screwed it down to the case mouth, then screwed it in more 1/4 of a turn (okay?).

Huge difference and did not spin, at least on a few of them. So then I believe you brought the final piece to this puzzle: RESIZE THE CASES IN STEP 1... and give it another shot, which should perfect it. Well, I don't want to get too confident just yet, I'll tell you in a bit when I get back over there.

*** FYI to clear the air on the RCBS expander issue. Why did I toss it and go with the Redding Premium Expander? Easy... the RCBS bolt could not dial in precise stuff like .002 and it did not have the secondary ledge in the die that creates a clear flare line. For me, it was the difference of night and day. In fact, I was so impressed because literally in 10 minutes I was already getting great results. Likewise, due to this experience I am considering replacing with Redding on the other stuff as well.
 
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