"coke bottle" shape when reloading 9mm: good, bad, ugly?

Things have really gone up, I bought my RCBS dies set sometime around 2005, I know I paid less than $45.00 for the whole set.
I saw it had a tapered resizing die and guess I though all brands were tapered. Obviously not.

9mmepiphany said:

We all need to evaluate our own needs and weigh the cost/benefit of a purchase to meet those needs.

My loading buddy thought the $120 Mighty Armory Sizing die was worth it for what he wanted...plus he was already lubing his 9mm cases, with lanolin/alcohol mix, so there wasn't an added step (Sidebar: straight wall cases dies are $20 less)

I use a Redding Dual Ring Carbide Sizing die ($115) for loading .38Spl and think it well worth the extra cost for my purposes...I got mine on sale for a lot less

I think of the cost of RCBS dies as the median to compare cost against, as opposed to the Lee dies which I consider entry level. That doesn't mean I'm a die snob, I use Lee dies when they offer features not available on other dies

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I think the RCBS dies do offer great quality at a good price point for their features. If I cared about the coke bottle look, that’s what I’d buy.

9mmepiphany said:

We all need to evaluate our own needs and weigh the cost/benefit of a purchase to meet those needs.

My loading buddy thought the $120 Mighty Armory Sizing die was worth it for what he wanted...plus he was already lubing his 9mm cases, with lanolin/alcohol mix, so there wasn't an added step (Sidebar: straight wall cases dies are $20 less)

I use a Redding Dual Ring Carbide Sizing die ($115) for loading .38Spl and think it well worth the extra cost for my purposes...I got mine on sale for a lot less

I think of the cost of RCBS dies as the median to compare cost against, as opposed to the Lee dies which I consider entry level. That doesn't mean I'm a die snob, I use Lee dies when they offer features not available on other dies

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A lot of my die sets are mixed brand. Some things I like about each brand recommend them so I get sets, mix them for what I want to do, then either give away or hang onto the odds-n-ends until I have a purpose for them. My .45ACP die set, for example: Lee Universal Depriming Die, Hornady sizing die, Lee powder-through expanding die, Hornady seating die, Lee Factory Crimp Die, both Lee and Hornady shell holders. Oh, and I prime on a Frankford Arsenal hand primer. I make good .45ACP and .45AR ammo without any worries because each die does exactly what I want and nothing that I don't. I know, I'm kinda lazy and weird that way but, it works for me. YMMV.

Bottom line: if you find dies that do what you want, the way you want it, it's okay to mix brands and styles to make your own set.

GeoDudeFlorida said:

A lot of my die sets are mixed brand. Some things I like about each brand recommend them so I get sets, mix them for what I want to do, then either give away or hang onto the odds-n-ends until I have a purpose for them. My .45ACP die set, for example: Lee Universal Depriming Die, Hornady sizing die, Lee powder-through expanding die, Hornady seating die, Lee Factory Crimp Die, both Lee and Hornady shell holders. Oh, and I prime on a Frankford Arsenal hand primer. I make good .45ACP and .45AR ammo without any worries because each die does exactly what I want and nothing that I don't. I know, I'm kinda lazy and weird that way but, it works for me. YMMV.

Bottom line: if you find dies that do what you want, the way you want it, it's okay to mix brands and styles to make your own set.

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My 9mm work is all w/Lee while my 45ACP is mix and match similar to yours EXCEPT shell holders. I never mix shell holders because I don’t trust they are identically sized.

CoalCrackerAl said:

Hmmm... never came across that when loading 9mm. Have a pic of it?

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Me nether and iv'e loaded thousands if 9MM Seems to me that with that shape the brass would be worked more just to fire form it to the chamber. The top bulge i can see but not the pinch in the middle.

Tons of good info here...but I just want to be sure.

I am using a Dillon sizing die, and my loads look like the picture Shak3s1977 posted. My 9mm loads with RMR 124g FMJs at 1.13 all plunk in my guns. All my rounds go through an Armanov case gauge. 1000's of rounds shot with no issue.

I purchased a 9mm threaded barrel for my Glock 19 from Foxtrot Mike Products. (After I received the barrel, I did a plunk test, but now I know I was wrong...) I took the barrel to the range and was able to fire two rounds through it. The first round chambered by dropping the slide. Second round wouldn't chamber and the slide would not move. The RSO forced the slide and was able to shoot the round. I tried again, same result. The range armor took the gun and got the round out. Then I shot a box of factory ammo through the barrel and can. No issue.

Upon closer inspection, after reading this thread, factory rounds plunk in the threaded barrel, and my reloads will not plunk, not by much, but they don't plunk. I am concluding that my threaded barrel has a tight chamber.

If I understand this thread:
The Lee steel resizing dies will size the case so the 'wasp waist or coke bottle shape' is not present?
Older Lee carbide dies will size the case so the 'wasp waist or coke bottle shape' is not present? How old? I have a set from 2014ish...
The RCBS Carbide Sizer Die - Group B will size the case correctly with out the bulge?

I am thinking I need to buy the RCBS die. What do you think?

I would recommend the RCBS sizer die.
But first, measure your reloads to see what part of the case might be sticking. Or cover a case with black sharpie and try to chamber it. You might find you can adjust your Lee die setting to work for you.

Lee sizing die. Measure fired brass, size, measure again. Easy to see if die applies a taper. https://www.thehighroad.org/index.php?threads/does-a-lee-full-length-sizing-die-taper.795022/

You don't have a tight chamber, your bullets are likely hitting the rifling.
Your Armanvo case gauge is notorious for being tight, highly doubt a drop in glock barrel is tighter.

Just dropping the round into the barrel doesn't mean jack imo.
Does the round spin? If it won't spin easily its hitting the rifling and you need to adjust your setting depth.

IMO, rmr bullets when compared to other bullets have a shorter fatter profile that isn't as forgiving.

Bosn Ski said:

Tons of good info here...but I just want to be sure.

I am using a Dillon sizing die, and my loads look like the picture Shak3s1977 posted. My 9mm loads with RMR 124g FMJs at 1.13 all plunk in my guns. All my rounds go through an Armanov case gauge. 1000's of rounds shot with no issue.

I purchased a 9mm threaded barrel for my Glock 19 from Foxtrot Mike Products. (After I received the barrel, I did a plunk test, but now I know I was wrong...) I took the barrel to the range and was able to fire two rounds through it. The first round chambered by dropping the slide. Second round wouldn't chamber and the slide would not move. The RSO forced the slide and was able to shoot the round. I tried again, same result. The range armor took the gun and got the round out. Then I shot a box of factory ammo through the barrel and can. No issue.

Upon closer inspection, after reading this thread, factory rounds plunk in the threaded barrel, and my reloads will not plunk, not by much, but they don't plunk. I am concluding that my threaded barrel has a tight chamber.

If I understand this thread:
The Lee steel resizing dies will size the case so the 'wasp waist or coke bottle shape' is not present?
Older Lee carbide dies will size the case so the 'wasp waist or coke bottle shape' is not present? How old? I have a set from 2014ish...
The RCBS Carbide Sizer Die - Group B will size the case correctly with out the bulge?

I am thinking I need to buy the RCBS die. What do you think?

Click to expand...

Not really. It seems more likely you just need to work up a load that works in your new barrel. 1.130” is typical for that bullet but it sounds like the FMP barrel is not typical. It could very easily need a shorter COAL. Adjust the COAL and powder charge for that barrel and you will be off to the races.

Oh, and just to be sure, drop a freshly resized case into the chamber of your new barrel. It should seat to the chamber and fall out easily with just gravity. If it doesn’t, then you might need an undersized die.

I agree with the previous posts. The Dillon die and it's wasp waist is not your problem. A new die won't fix your problem.

I would make a dummy round( no powder, no primer) at your 1.13 oal and cover the entire bullet and case with a black sharpie as drband suggested. Remove the barrel from the gun, drop the dummy round in barrel and I usually use a pair of pliers to grab the rim of the case and twist the dummy round while in the barrel. Remove the round and depending on where the marker is rubbed off will indicate your problem.

Marks on the bullet usually indicate your c.o.a.l is too long and the bullet is hitting the rifling in the barrel.

Marks by the case mouth usually indicate the flare wasn't removed all the way, or the case buckled while seating and crimping at the same time.

Marks on the body of the case usually indicate a sizing problem.

Bosn Ski said:

Tons of good info here...but I just want to be sure.

I am using a Dillon sizing die, and my loads look like the picture Shak3s1977 posted. My 9mm loads with RMR 124g FMJs at 1.13 all plunk in my guns. All my rounds go through an Armanov case gauge. 1000's of rounds shot with no issue.
I am thinking I need to buy the RCBS die. What do you think?

Click to expand...

Read through this and most but not all of my loads have some similarities to the pictured. Some are more pronounced than others.

That said, most of the cases I load were purchased as once fired from here or there and initially were just mixed range brass. Some were from a police training range. I used a "small base" die which takes care of whatever sized chamber they were fired in. The chamber on one of my 9's is tight, the other not so much. Just easier to load for one and shoot in both.

The main issue I found was the flare plug was adjusted a bit deeper than need be. This gave a tiny bit of swell to the case just behind the crimp. This resulted in just what was explained, the slide might go all the way, or might not. That depended on the brand of case as much as anything else. It took a marker to finally find it as it was such a small area.

I use both RCBS and Lee die sets and initially thought this was the issue until I happened to find it doing it with both. First thought was I had put too much crimp, but using plated bullets it was easy enough to check. After that was when I got out the marker and started coloring.

As for the wasp or coke bottle shape, I've had that on revolver loads for so long it just don't matter anymore. They always go boom and most times hit where I aim, and it's usually me that is the weak link.

Some headstamps "hour glass" worse than others in 9mm, possibly due to thickness of the brass... but I truly hate it when it's assymetrical..
I noticed that brass that's been previously fired out of a Glock chamber or my SIG p228 chamber (which is even bigger than a glock) this problem then becomes worse when the resizing process happens again (which is straight walled, not tapered) I eventually learned to raise the resizing die so that the rounds cycle in my intended chamber reliably, but no more. I don't go all the way down to full length. This still gets plenty of the desirable neck tension, but not so much you get the bulge.
If neck tension is too much, you can get crooked rounds if your seater stem is a basic one, or deform noses/meplats....I've made every mistake in the book over the years...so much help from folks here on THR straightened me out, and straightened my ammunition too.

I also noticed that the rounds that "hourglass" or "coke bottle" pass the "plunk test" with flying colors, often they even "rattle" in the chamber. This tells me that the resizing die might go to the smallest possible tolerances for the caliber. This might mean better more consistent reliability in the thousands of different platforms of 9mm that are out there.

Walkalong said:

Yep, ever since I purchased an EMP with a SAMMI minimum chamber I have been checking all of my sized 9MM cases with a Wilson case gauge.

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I was under the impression that the Wilson Case Gauges were for headspacing only, not SAAMI chamber dimensions (?).

It's not as pronounced with my Dillon dies than it is with my RCBS carbide dies. It's the nature of the beast though...it's a tapered cartridge, basically being resized as a straightwall, then have a bullet seated. It certainly makes setback less likely;-) It even looks like this with brand new starline brass.

9mmepiphany said:

AJC1 said:

It's taking a tapered case, making it a straight wall and cramming a bullet in.

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Carbide dies are over resizing your 9mm cases. The carbide ring in the dies are trying to turn your tapered case into a a straight walled case.

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But not all 9mm carbide sizing die has straight carbide sizer ring, which tends to leave a pronounced resizing mark towards the base of case which is wider, since 9mm is a tapered case.

Lee carbide sizer ring is tapered and won't leave resizing mark on case towards the base of case. Below is picture of cases resized with Lee carbide sizing die and tapered carbide sizer and resized cases have smooth "tapered" lines to case base instead of narrowing from straight carbide sizer dies.



But Lee sizing dies tend to reduce brass to smaller OD and further down towards case base so I deem them essentially mild/lite undersize dies (U-dies). So even with the tapered carbide sizer ring, smaller resized case neck will show slight bulging of case neck around the bullet base like these, which is sign of good neck tension to prevent bullet setback.



Note sharp 90 degree edge of case mouth from having .377" taper crimp applied to .355" sized bullet (To headspace with the chamber) and smooth gradual taper of case neck from taper crimp die.

I get the same thing Live Life showed (but without as many quality pictures) with my Lee dies. They do get a coke bottle thing going but you have to hold them up to a uniform background to see it. Same thing happens in straight-walled 9x18 and 45 AutoRim too. The plus side is no setback. I was worried about setback on a load last year so I tested and measured dummy rounds in both of my 9 mm pistols. I found I got no setback and in fact had set-forward (is this a term, if not I’m claiming it) from the inertia of chambering.

I also notice that only certain bullets do it, usually jacketed usually ones with a very crisp squared off base do it the worst.
What I do know is that no offering from x-treme bullets does the coke bottling. Their standard 124 gr hollow points I use the most, then the X-def 124gr 2nd. I have no need to look any further.

That coke bottle or hourglass shape is pretty common with a few sets of my Dillon dies. They shoot fine and I can't really tell it it reduces case life or not. It does take a little getting used to.