The asymmetrical "Bulge" on 9mm. Why?

[Palladan44]

Ok.. Dillon 550B, factory dies, 9mm Luger...
(Not talking about bulging on once fired brass near case head from unsupported chamber, but the bullet bulging out the brass slightly more on one side than the other)

Certain Bullets may be slightly larger than others and thus will have more "case tension" and show the "bulge" through the brass. I dont mind it at all... if its symmetrical all the way around. But often it is not. Often the bullet bulges on one side of the case more than the other.. In rare cases the cartridge will be assymetrical enough to go into the chamber sticky. But, 99.9% of them are still in spec. and they function fine. Some of you may say "well what are you worried about then"???.. Well im a bit of a perfectionist, and this assymetrical bulge is annoying me...

Ive uses both the flat and round orphose of the seater stem with the same result. Ive used different amounts of belling with same result. Ive used different lock rings, and always raise the platform on the case to adjust as directed. Same results. Ive shimmed the toolhead to close the small gap between the machine and the toolhead with the same result. Its kind of annoying, as Im kind of a perfectionist with my reloading and feel ive perfected everything with these loads. I just cant get over the assymetry it really bugs me!!!

My next step is to get different resizing die, one which may size to slightly larger specs, and possibly have slightky less case tension.
Also, I may try new toolhead and seating die.
I cant get over how this happens with 9mm, but have no problems with 38 special, 357 Mag, 44 mag or 10mm. Just this 9mm giving me this problem with Winchester 147 Jacketed. And Zero 125gr jacketed bullets.

One last thought is this... if the once fired brass im using has the Glock bulge, or was fired in another gun with an unsupported chamber on the bottom, often the brass can be bulged on one side near the case head (you all know this already) I know some are fans of bulge busting 40s&w and 10mm, but I kind of think that because 9mm is a parabolic case, that there is no bulge busting or push through resizing 9mm, is that correct? All im doing is resizing on standard Dillon die.... Is there a chance that the brass is still slightly Assymetrical and the seating is thrown off due to the slight deformation of the once fired brass?

Help on this mystery would be greatly appreciated. (As you can see in this image, there is a greater protrusion on the right side of the case than the left)

 

[Walkalong]

Better alignment will help that. Starting bullets straighter and a sleeved seater.

I had that issue in .45 ACP until I got a Redding comp seater.

 

[fxvr5]

Better alignment will help that. Starting bullets straighter and a sleeved seater.

I had that issue in .45 ACP until I got a Redding comp seater.

Yes, as Walkalong notes, it's just an alignment during seating issue. You can get a Redding competition seater to fix it, but it doesn't matter if the round still chambers. If some are not chambering, that's a good enough reason to get the Redding competition seater. But just for aesthetics? No.

Below is an article that covers the issue.
https://americanhandgunner.com/gear/crooked-seated-bullets-and-accuracy/

 

[PO2Hammer]

Tilted bullets are more than an aesthetic issues if you're serious about accuracy beyond 25 feet.

 

[fxvr5]

Tilted bullets are more than an aesthetic issues if you're serious about accuracy beyond 25 feet.

It doesn't seem to matter for the typical handgun at typical handgun distance (25 yards) according to the information at the link.

 

[PO2Hammer]

That link does not mirror my experience or opinion.

 

[Palladan44]

That link does not mirror my experience or opinion.

Fortunately the accuracy isnt noticeable in my case. I believe the article to be mostly accurate, but I believe your case as well. I believe as soon as the bullet meets the rifling it is stabilized/equalized if it was slightly angled. There is the possibility of differences in pressure due to the bullet having different amounts of friction initially as it leaves the case. So although the bullet is stabilized it may have a greater extreme spread in pressure and thus greater extreme spreads in velocity than ammunition that is more uniform. Again, its just a theory.

 

[Blue68f100]

Is it on all stations or just a select few? Could be the shell plate is not aligning as it should.

 

[PO2Hammer]

Handloader magazine did a test with tilted bullets (a revolver caliber IIRC)
Looking at recovered bullets they found evidence of what they called 'skidding', uneven rifling impressions, showing that tilted bullets do not 'straighten up' when they're forced into the rifling. Don't recall their accuracy results though.

I started 9mm with the Lee 'deluxe' 4 die set.
My handloads with premium JHPs were noticeably less accurate at 25 and 50 yards than any factory ammo.
I never had feeding issues, but the lopsided bulge was present on some rounds no matter how careful I was.
Invested in a Redding comp seater and wow! instant improvement, no more bulges and accuracy was as good as anything I've ever bought.

Not saying you need an expensive seater to make good 9mm ammo,
just saying some dies and some bullets don't play well together, and accuracy at distance will suffer.

 

[packetloss]

Also with Dillon dies make sure you are using the right seater die insert side. Some HP bullets seat better with the round nose side as opposed to the flat point side. Take out the insert and sit a bullet on either side and see which side holds the bullet better.

 

[rfwobbly]

IMHO your issue stems from the loose fit of the bullet in the Dillon seating stem. A correct stem insert should center, straighten, and align the bullet as it enters the case neck. Luckily the Dillon seating stems are replaceable and you can acquire another that fits the bullet's ogive a bit tighter.

I make stems for the conical and SWC shapes, but not the rounded ogive like you show. If you know a hobby machinist, maybe he'd be willing to help you.

 

[nettlle]

I see this slight bulge when reloading but never had accuracy issues because of it. Just out of curiosity once I used micrometers to check the outside diameter of the bulge and I then checked the outside diameter of a factory round. Both diameters were the same so I figured nothing needed to be fixed.

 

[NMexJim]

Increasing your flare just a bit can help get a bullet started straighter.

 

[Walkalong]

Better alignment will help that. Starting bullets straighter and a sleeved seater.

I had that issue in .45 ACP until I got a Redding comp seater.

I forgot to add a Lyman M-Die or equivalent for an expander coupled with starting bullets straighter and using a sleeved seater.

 

[tightgroup tiger]

I use M-dies exclusively for neck sizing dies, they are the real thing. Pretty hard to get the bullets set crooked with them.

 

[nettlle]

Be hard to use an M-die on a 550b

 

[FROGO207]

The standard answer is to make sure you flare only enough to start the bullet or you loose neck tension. I found that if you flare enough so that you can set the bullet into the casing and after pushing down lift the brass it will seat straighter. You may have to reduce the diameter of the bottom of the seater plug to keep neck tension but it works for me withoit buying more stuff. Get a different expander plug to experiment with if you are worried about ruining the origional.

 

[nettlle]

And it may not be a problem at all. If the rounds are accurate and feeding well maybe best left alone. The bulge is cosmetic to me and although I love Redding stuff I'm not going to shell out another $100.00 for a die just to make my finished rounds look better.

 

[lordpaxman]

Tagging in. I’m hoping the OP will let us know how well these rounds perform.
I noticed the nickel case in the picture, is all your brass one HS, and what is it? I’ve had Speer nickel cases be more of a problem with bulging than other HS. This is with a 147 RN blue bullet.

 

[DukeConnor]

Be hard to use an M-die on a 550b

There are after market powder funnels for dillon that mimic the m die expander.

 

[mokin]

I've had bulged cases as described in the OP as well. Although it has never bothered me - as long as it goes "plunk", there is a lot of good information regarding other aspects of handloading and shooting here. Thanks guys!

 

[ctgrizzly2hunt2]

This is what I do when I seating any bullets, I lightly start them and release handle when it’s about 1/4 way then I give the brass a 1/2 turn to complete the process. That seems to help me on that condition.

 

[Palladan44]

And it may not be a problem at all. If the rounds are accurate and feeding well maybe best left alone. The bulge is cosmetic to me and although I love Redding stuff I'm not going to shell out another $100.00 for a die just to make my finished rounds look better.

I wish the Redding comp. Die was available at only 100$ right now. In fact, I cant even find one in stock anywhere.

 

[AJC1]

Is there a difference between the hornaday custom grade and the redding in how the sleeve works or is designed. I know the names are not on par with each other but availability may be better.

 

[Walkalong]

I have both, the Redding works better, and is easier to read. Big price difference though, and if you already have a Hornady seater, you can buy just the top to add to it.

I added marker to the Hornady seater so I could read it.