Case bulge on one side when seating?

[jcerillo70]

Hi,

Im loading for Uspsa major

40sw with cz tactical sport orange

you can’t really see it but I can “feel” it. It’s only on one side. I thought it was very strange, but I never loaded 40 before. So I stopped to seek help before I continue.

I’m loading 180gr acme hi-tek rnfp
4.6/4.8/5.0 -> Vv n320
@1.126 oal

My books don’t have n320 data for coated/plated bullets- but from what I’m reading online 4.6-5.2 seems to be where everyone is loading. Oal between 1.18-1.135

Any insight on this bulge and how to fix it if needed is greatly appreciated

 

[AJC1]

Use an m style expander to help seat them strait.

 

[Walkalong]

Doesn't look real bad, but @AJC1 gives excellent advise, and I'll add used a sleeved seater, but you still need to start bullets as straight as you can, and the M die type expander really helps with that.

 

[jcerillo70]

Use an m style expander to help seat them strait.

for the time being, do you think I can make a bach of each, to test charges and find my load “powder wise”while I wait for the m die to come

 

[jcerillo70]

And I guess your saying it’s a seating problem because of the flat tips? my Redding micrometer die makes it worse, so I took my lee dies out. The also have round seating plug but it works better for some reason

 

[fxvr5]

Don't rush out and order an M die. First:

Do the bulged rounds fit in your chamber? If so, there's no harm done.

Even crooked seated bullets don't seem to affect accuracy at normal handgun shooting distances.

https://americanhandgunner.com/gear/crooked-seated-bullets-and-accuracy/

So, you might be able to ignore it. Lots of us do.

 

[FROGO207]

Something to check is if your brass are centeted on the ram. A crooked foundation will never make a good skyscraper. If you get dirt in the shellholder or in the mounting groove on the ram things will never be straight. Clean those areas first. Then a stem that fits the bullet however you get there. Those rounds will probably work if you can plunk them successfully.

 

[AJC1]

If you dont like the m die expander route and you shoot the same bullet always a custom seater plug will also help. They run about 25 bucks. I load rmr matchwiners with a standard wadcutter stem and dont have any issues. You may also try a little more flair which will start you deeper with hopefully a little deeper alignment

 

[jcerillo70]

Something to check is if your brass are centeted on the ram. A crooked foundation will never make a good skyscraper. If you get dirt in the shellholder or in the mounting groove on the ram things will never be straight. Clean those areas first. Then a stem that fits the bullet however you get there. Those rounds will probably work if you can plunk them successfully.

Yes I plunked every one and they go perfect.
I loaded 15 of each load, I’ll try them out tomorrow.

I am using a lee shell holder and it has a lot of slip. Any recommendations for tighter shell holder?

 

[jcerillo70]

If you dont like the m die expander route and you shoot the same bullet always a custom seater plug will also help. They run about 25 bucks. I load rmr matchwiners with a standard wadcutter stem and dont have any issues. You may also try a little more flair which will start you deeper with hopefully a little deeper alignment

Which custom seater plug do you recommend?

 

[fxvr5]

If they fit in your chamber then there's little reason to buy an M die. It's money spent for something you don't need. This might apply to other parts as well. Why spend money on stuff that won't make a practical difference. If your gun can't tell the difference, imperfect looking ammo will shoot the same as perfect looking ammo.

 

[Jonny V]

I have this same problem with 45-70 rifle loading...I'm thinking it's because the bullets are being seated a little crooked. Once seated that way and fired, they'll stay going crooked all the way down the bore and out into the air. Kinda like a quarterback throwing a "wounded duck" pass...not likely to matter for short range, but as the range stretches out maybe it might.

I'm switching out die sets to Whidden and getting rid of the RCBS. The expander die is very important (as mentioned above) and also using a sleeved seater die with a close fitting plug. I'm hoping this helps me out, we'll see I guess. I'll be interested how your issue resolves as well!

 

[fxvr5]

I have this same problem with 45-70 rifle loading...I'm thinking it's because the bullets are being seated a little crooked. Once seated that way and fired, they'll stay going crooked all the way down the bore and out into the air. Kinda like a quarterback throwing a "wounded duck" pass...not likely to matter for short range, but as the range stretches out maybe it might.

It seems it would have to be one very loose barrel for the bullets to stay in the same crooked orientation.

 

[Jonny V]

It seems it would have to be one very loose barrel for the bullets to stay in the same crooked orientation.

Doesn't have to be as loose as it might seem...because the bullet is so much softer than the steel, it can be deformed in the firing process. At least this is how my more experienced long range friends explain it. Might not notice anything under 500 yards or so (rifle shooting) but most competitive rifle matches start at around 500 and go out to 1200-ish (for 45-70's at least).

I'm not sure the dynamics with pistol shooting matches, but the bulge in the photo looks the same as the problem I've had for a while now, just a smaller case.

 

[9mmepiphany]

And I guess your saying it’s a seating problem because of the flat tips? my Redding micrometer die makes it worse, so I took my lee dies out.

I'll let him answer the question you've asked, but I'd like to add that it isn't likely that the flat tip is causing the problem.

These kinds of one-sided bulges are usually caused by the bullet not being placed/started straight into the case mouth. When contacting the seating stem the bullet moves in the direction that it is oriented in until enough of the bullet encounters enough neck tension to somewhat straighten out. The recommendation to get an M profile expander is that this die creates a "seat", as opposed to a flare/trumpet, in the case mouth to help hold the bullet aligned with the case body.

I'm a bit confused about the problem being worst when using the Redding die. My Redding Competition Seating die doesn't contact the nose tip of the bullet at all. After the sliding sleeve has aligned the case and shank of the bullet inside the die, the edges of the seating plug contact the bullet at it ogive to push it into the case. Do you have a different style of micrometer seating die from Redding?

 

[fxvr5]

It's also worth noting that the article I linked to says that bullets can even end up crooked using the Lyman M die. In that article the author says that the best alignment results were with using just the Redding Competition seating die alone.

 

[9mmepiphany]

In that article the author says that the best alignment results were with using just the Redding Competition seating die alone.

Could be true. I was just getting frustrated with being unable to seat bullets without shaving coating...my first lead bullet loads for .38Spl...that I went whole hog in looking for a solution.

I went with the Redding Dual Ring Carbide Resizing die, their Expanding die (which had copied the Lyman), and their Competition Seating die. I did resist getting their Micrometer Crimp die

 

[jcerillo70]

Could be true. I was just getting frustrated with being unable to seat bullets without shaving coating...my first lead bullet loads for .38Spl...that I went whole hog in looking for a solution.

I went with the Redding Dual Ring Carbide Resizing die, their Expanding die (which had copied the Lyman), and their Competition Seating die. I did resist getting their Micrometer Crimp die

thats my exact problem with the micrometer die, it shaves off the coating on the bullets. So I had to go back to the lee

 

[tightgroup tiger]

Just because it's happening in the seating die doesn't mean the seating die is causing it. If you don't have enough flare your going to shave your bullets in the seating die, no matter what brand you use.

If you are putting to much taper crimp on your 40 S&W cases, you will shave lead also because the bullet is still moving into the case when the flare is closed up.
You want the more flare on the expanding die and just enough crimp to straighten out the flare on when seating the bullet.
I also use an M-Die profile expander. I run it in deep enough that I go past the step profile and put just a little trumpet flare on the case.

This keeps me from shaving lead and still gives me a straight ledge to seat the bullet in, You still have to try hard to set the bullets in the cases straight.

If your round nose bullet profile has the thick edge around it like mine does, it should seat flat nose bullets fine as it should still contact the outer part of the flat nose.

When seating I will just straighten out the flare, but I also use a dial caliper to tell me when the flare is all gone on the shortest cases.
I will close it up on the case just at the base of the bullet and slide it up the case to the top. Watch the dial on the calipers and if it moves open at the crimp you aren't taking all the flare out.

Then my dies don't shave lead at all.

It's a delicate balance of enough flare to get the bullet seated without scraping and just enough crimp to not close the flare up on the bullet to soon until just the last second.
I would also recommend you get a ammo check gauge and run all your rounds through it before shooting them. The ammo check gauge I use is a Lyman and it will catch the cases that the flare is still open a few thousands on. That gauge also helps me set my seating die correctly with coated bullets.

 

[9mmepiphany]

thats my exact problem with the micrometer die, it shaves off the coating on the bullets. So I had to go back to the lee

Okay, that isn't a seating die issue. You're not expanding the case mouth enough

 

[Bill M.]

I like the Redding competition seating die. For my .357 I had trouble with the competition die shaving a little of the coating. I switched to a Redding expander die and the problem went away. The competition seating die seemed to push the bugle like flare from the Lee die back in a little while seating the bullet but the shape of the flare from the Redding die is better and the combo works perfectly. At least my bullets seem centered, straight, unshaved, and tightly gripped.

 

[243winxb]

Fat bullets bulge cases. Bullet diameter: .400 " Seating dies are designed for jacketed bullets.

Your seem to be ok. As long as they function.

A seating dies ID may remove the bell to soon. Coating gets shaved. Open the ID of the seat die. Dont remove the taper crimp section.

Get a plug that fits bullet nose or works off the ogive.

 

[Walkalong]

thats my exact problem with the micrometer die, it shaves off the coating on the bullets. So I had to go back to the lee

I have a couple of Redding Micrometer Seating dies, and they are great. That said, if a seater (any seater) die body ID is tight enough it can remove some flare, and if it removes enough for the bullet being used, it can then shave bullets, especially if the bullet is started crooked. I have said it a bunch of times, the sleeved seaters aren't magic, and if the bullet is started too crooked, they can't completely fix it. That said, they are great if you give them half a chance and start them as straight as you can. And me, I like straight ammo, regardless if a test says crooked pistol bullets can still be accurate. We know crooked rifle bullets don't shoot as straight, and I am an old Benchrest shooter, so I llke straight ammo. And it looks better, even if it doesn't shoot any better.

So check to see if the sizer wasn't straightening out some of the flare. I have one that does it enough that I can't use coated bullets in it.

 

[AJC1]

One thing that you can do if money is not tight is to see if they make a set of cowboy dies. I dont load that caliber so I dont know if rcbs makes a set for 40 or not. They are specifically made to deal with lead and have the correct dimensions for the larger bullets. This would be even more important on an older gun with looser tolerances.

 

[Ru4real]

@jcerillo70

More often than not, the die is fine in this situation where there is a bulge on one side of the case. It’s not the die.

Most often the cause is that the case head is not in perfect alignment with the centerline axis of the die. As the case goes up into the die, something has to give and it’s the wall of the case. The amount of bulge you are seeing is the amount of misalignment between the case head “pinned” in the shell holder and the centerline axis of the die.

Causes of misalignment, visible in case bulge are, from most common to least common:
1. Tolerances in shell holders and loading ram shell holder receiving sockets
2. Tolerances in ram shaft bushing
3. Tight tolerances between ram shaft and ram shaft bushing (more common in new presses)
4. Poorly constructed press
5. Poorly constructed die

Consider that 0.001” miss alignment between shell holder and centerline of die will result in a “big” bulge because the brass is smooth and shiny. It stands out like a turd in the snow.

If everything is close to perfect, you put the case all the way into the shell holder with loose bullet sitting on top, ram goes up and bullet seats concentric to centerline axis of case and case head. No visible bulge.

What if when you put that case all the way into the shell holder, you actually put it in 0.001” too far so that is now not in alignment? Some of these misalignment problems can be fixed using additional loading steps and techniques when you encounter them.

Sometimes cases are strong enough to slide the case head where it needs to be for alignment (caliber dependent), sometimes there is no room for the case head to move (tolerance stack up) and sometimes things are near perfect.

Unfortunately, popular opinion is to “Buy a new die”.