9mm after fired outline of bullet and lower case bulge Help!

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marathonrunner

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Guys, after firing my handload using brand new Starline 9mm brass, I am seeing the outline of the bullet and a slight bulge at the bottom of the case that is uniform. The primer looks normal, no nicks on rim where extractor extracts. Am wondering if this is normal. When loading there is no bulge or outline of bullet. I am using 124XTP hornady bullet
 
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pictures might help but a slight bulge near the case head is often normal depending on pressure generated & chamber dimensions
 
Semi-auto ramped barrels have an unsupported area, the amount of bulge in the case depends on how far past the webb the unsupported portion extends.

Glock 40 S&W are known for extreme bulges. 9mm usually not so much.

Should be ok, but post a pic and we'll give you a dozen opinions or so.
 
I am using near max load using BE 86. The velocity is 1117fps and seems to be standard pressure. The bulge is near the rim
 
How many reloads have you shot.....

The load doesn't SOUND excessive. What kind of history do you have making reloads for this gun? What type and year of gun is it?? What experience do you have with BE-86. (I have none).

I don't want to blame the brass right off the bat, but I've seen some some quality issues with Starline and wonder if this might be a soft batch.

I'd mostly be concerned with the bulge at the rim.
 
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Your load sounds fine. I load 4.1 gr. Win 231 under a 125 gr coated bullet which I chrono at 1100 fps with no pressure signs at all. My guess is the chamber in your gun is over-sized or not finished completely.
 
Yet another MM Emergency.

Don't ever touch the RED button!

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Yep another crisis. The 9mm case is not straight walled like most
other auto pistol ctgs but is tapered a little. The "uniform bulge near
the rim" you are seeing is probably where your sizing die stopped,
assuming you sized the new brass before loading it. But...you didn't
say and your load isn't hot by any means so your cry for help is ...?
 
1. Starline 9mm brass new. Only resized ones that had bent case mouth, all others passed the ker plunk test using my gauge case

2 Gun Used was Walther PPS M2. After fired, brass case will not pass the gauge case test and diameter of case nearest the bottom is .394 but primer shows no signs of overpressure at all. However brass fits inside PPS M2 chamber just fine. PPQ also seems to fit fine. However, my G34 the spent case brass will not go in-only three quarters of the way. Hence, I am thinking PPS has a larger diameter chamber but then wouldnt you think 115gr would also get bulged but it does not

3. The 115gr XTP does not seem to bulge at all after fired. When creating new 124gr XTP, bullet is perfect, no bulge and no outline of bullet near case mouth.

4. My cry for help is all these conditions normal? I am wondering if I shot a box of Winchester PDX1 or Speer 124gr would I also after firing round see brass bulge. I do think the chamber in PPS M2 seems a bit oversized.
 
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I suspect all you are seeing is what is termed "fire forming" your brass to the chamber. You may want to double check your OAL, but I suspect thats within spec. Try firing some factory ammo, and see if you have similar cases to your reloads.....
 
So, I had the same issue and was dumping brass like crazy after pulling bullets. However, some suggested, as I collect brass at matches, that there is something called a Glock bulge.
I use an undersized sizing and priming die and it has eliminated the situation while loading.
First, I deprimer and size, clean and then run again through my regular Dillon 550b.
2 or 3 out 200 now won't size.
Highly recommend a case gauge, I use one that does 100 rounds at a time.
Suspect your situation is how much you are loading in powder, near max that's responsible for this normal occurrence.

Sent from my SAMSUNG-SM-N910A using Tapatalk
 
This is what I think. Alliant Powder BE86 has a recipe for 5.9gr and OAL of 1.120 which brings a velocity of 1175. Hornady told me to use their OAL of 1.060 with their 124XTP 9mm bullet because that is what was tested. They also told me Alliant is basically giving a generic seating depth where Hornady they worked it out where 1.060 seems best but to me that sounds too deep. Hornady also advised me to subtract 5% from Alliant's powder charge of 5.9gr of BE86 and start from their.

So taking it one step further, they have a starting charge of 5.3 with a max charge of 5.9gr for BE86. Based on what Hornady is telling me, I should be starting at 5.6gr which is at the lowest of the spectrum and the current load of 5.6gr seems to be causing the lower part of my 9mm brass closest to the rim to measure .394. You can visually see it is bulging more than a typical 115gr round. I have never seen a case that bulged like that. Then I see the outline of the bullet as well. Keep in mind when I make the bullet from scratch, it is perfect no bulge or no outline of bullet. Recoil seems no different than a standard pressure Critical Defense 115FTP round or my practice reloads. I am thinking that is still a hot round and close to +P pressures so maybe cases will do that with these rounds. I have not seen any self defense hollow points with velocity lower than 1100fps. I am thinking if I lower the charge, I will be more like .45acp velocity which would then be pointless to use a 9mm

@big stick not sure what fire forming is but don't think that is the case.
 
It sounds like you have a couple things going on. You need to:

Put the bulged cases back in your barrel to see how far they seated when fired.
Put a sized unfired case in your bbl to see how far it seats.
Measure the spent cases bulged and not bulged to see the difference.
Use the measurements from the non-bulged used/shot/spent cases (fire formed) and see if they are within saami specs.
Look to see if the bbl is properly throated.

It almost sounds like you had the oal too long with your bulged loads and the case/round didn't fully seat when fired. The tolerances on allot of these defense pistols are extremely loose with function being the priority. I've seen different wonder 9's function with loads 50/1000ths+too long (rim over the top of the bbl hood). That doesn't sound like much but with a tapered chamber that already has loose chambers it quickly becomes excessive.

Be safe and use good reloading practices, the ok/normal headspace is what you want with "jacketed" bullets. You want the rim of the case just below the hood of the bbl (around 20/1000th's). I load all my loads that way (jacketed or lead) in all of my defense pistols.



What you don't want to see when you put your fired (bulged) cases in your bbl when you line the bulge up to where it happened in the bbl is having the rim of the case look like the last picture above on the far right.

A little bbl 101:
Something the mfg's started doing a couple of years ago. They are omitting 1 simple step in the bbl making process, namely throating the bbl. A un-throated bbl, note the shape chamber end (flat wall) and the steep angle on the lands.



The same bbl after it has been properly throated with a throating reamer that takes less than 1 minute to do.



The chambers end is still there but the diameter of the beginning of the throat has increased. The throat is now long and tapers into the riflings. Doing this allows the bbl to accept larger diameter'd bullets along with chambering bullets that are crooked (not seated straight) and is allot more forgiving about a rounds oal.

Short chambers are very unforgiving. Just something to think about.
 
Jcalero said:
So, I had the same issue and was dumping brass like crazy after pulling bullets. However, some suggested, as I collect brass at matches, that there is something called a Glock bulge.
I use an undersized sizing and priming die and it has eliminated the situation while loading.
First, I deprimer and size, clean and then run again through my regular Dillon 550b.
2 or 3 out 200 now won't size.
Highly recommend a case gauge, I use one that does 100 rounds at a time.
Suspect your situation is how much you are loading in powder, near max that's responsible for this normal occurrence.

Sent from my SAMSUNG-SM-N910A using Tapatalk
Click to expand...


No I do not think it is the "Glock Bulge" because the bulge is uniform and goes around the whole case and this only happens after firing round. 5.6gr of BE86 is midrange of the spectrum and 5% less than their max charge of 5.9gr. However, Power Pistol 5.6gr is almost maximum load. But the Power Pistol seems much weaker and less snappy than BE86. I think you are right that the pressure is close to a Plus P round. Yikes not sure I want to have any cartridge loaded to that level but I guess if I am making self defense loads, it has to be near Plus P. The other alternative I can make it at 5.4gr but then I will be near .45acp velocity which would make the 9mm basically a watered down .45. i think I am going to switch to Hornady's 115gr XTP because then I can be at the same velocity of 1117 and be a lower pressure round
 
Or you could move up to 147gr on 9mm and be closer to a 45acp power.
I load Bullseye, 3.8 or 4.0 on 147gr and get good defensive loads at 1050 fps.

Sent from my SAMSUNG-SM-N910A using Tapatalk
 
1. Always resize all brass; new, once-fired, or ancient.
2. No surprise that brass doesn't fit the case gage after firing. The case expands. The case gage is mostly to be used for measuring the completed round. (See 5 below)
3. A finished, complete, round is called a round or cartridge. The bullet is the projectile.
4. It's hard to tell what your "bulge" actually is without pics. But it is NOT unusual to see the outline of the bullet through the case on finished rounds. This is because you have sized the case slightly below the diameter of the bullet so there is a "friction fit" or case mouth tension that holds the bullet in place. So you actually have a slight narrowing or "wasp-waisting" of the case just below the bullet.
5. If there is actually a "bulge" down by the case head, it is fine if the sized case will fit the case gage. If it doesn't, try adjusting the sizing die slightly downward per manufacturer instructions.
6. It is very difficult if not impossible to "tell" or "feel" pressure within a cartridge without instrumentation. Just be confident that published data is safe. Also you cannot know what your velocity might be without a chronograph. All you can do is estimate. Ditto go with published data and don't speculate.
7. If the completed round will fit the case gage, and you are using published data, and you are using an OAL provided by Hornady for their bullet, you are good to go. Have no fear.
 
re: " it is NOT unusual to see the outline of the bullet through the case on finished rounds."

agree; I see it often enough in my otherwise perfect reloads, to consider it "common" if not "normal";

re: full circumferential rim-end bulge
Even adjusted 'full down' my Dillon 650 leaves a tiny space that the sizer die just doesn't touch, perhaps the last 1 or 2 mm. Neither does the Lee Factory Crimp Die, which for well over a decade, has satisfactorily modified whatever bulges it encountered.

About a year ago I had an unexpected kinetic event, which proved to be a 9mm case rim blow out, of unknown cause and no damage save a little powder fouling along with similar to my up-til-then-new underwear.

Examination by range officials concluded likely cause was simple multiple reloadings (unknown range brass) and eventual brass fatigue after probable repeated 'brass bulge'; ultimately it was of unknown cause but sensible conclusion of speculation.

I've seen similar 'rings' near bottom of slug in most pistol calibers I reload. They all fit in the case gauge, they all fit in the chamber, and none have give any observable functional issues.
 
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