Sizing die brass shavings

[CZSandW]

When running .357 mag brass (new or used) through the sizing die I end up with brass shavings inside the case and inside the die. New brass is Remington and Starline, die is Hornady (with titanium nitride insert), press is Lee breech lock. I’ve tried unlubed, and lubed (Hornady unique case lube). The sized cases don’t have any scratches or scuffs, and otherwise look fine. The photo shows amount of shavings after sizing 50 cases. I have sent the die back to Hornady, they inspected and polished and returned to me. I talked with Lee and they say it’s not the press because the casing never touches the press. The photo shows the amount of shavings after sizing 50 cases.
Has anyone experienced this before? Are these cases safe to use?

 

[jepp2]

Looks like the shaving are coming from the case mouth. Inspect them closely with good lighting and magnification.

 

[Bill Norris]

When running .357 mag brass (new or used) through the sizing die I end up with brass shavings inside the case and inside the die. New brass is Remington and Starline, die is Hornady (with titanium nitride insert), press is Lee breech lock. I’ve tried unlubed, and lubed (Hornady unique case lube). The sized cases don’t have any scratches or scuffs, and otherwise look fine. The photo shows amount of shavings after sizing 50 cases. I have sent the die back to Hornady, they inspected and polished and returned to me. I talked with Lee and they say it’s not the press because the casing never touches the press. The photo shows the amount of shavings after sizing 50 cases.
Has anyone experienced this before? Are these cases safe to use?
View attachment 1308838

I have seen this in 9mm with Lee dies as well. Never thought it was harming anything at the time. Ammo shoots fine.

 

[CZSandW]

Looks like the shaving are coming from the case mouth. Inspect them closely with good lighting and magnification.

I just looked at a couple dozen sized cases with a 10X lens. They look very uniform, no evidence of dragging or scraping off brass at mouth or anywhere among the case exterior. This is really driving me nuts. Haven’t seen it on 9mm using the Hornady 9mm die. I will load light using start weight powder and inspect each case one by one for cracks, bulging, etc.
do you know spec‘s for .357 mag case thickness? OD spec is 0.3790. Bullet dia is .357, so 0.379-0.357=0.22 / 2= 0.110? I’ve measured a bunch of case thickness and it’s anywhere between 0.0110 to 0.0085, do you know what is minimum thickness?

 

[CZSandW]

I have seen this in 9mm with Lee dies as well. Never thought it was harming anything at the time. Ammo shoots fine.

Okay, thank you. I’ll load some up at starting powder loads and monitor cases one by one.

 

[whatsupdoc]

That is not normal, I have never had this with any dies. That is a lot of brass shavings.

 

[fkimble@charter.net]

Two things caught my attention. The end of the case mouths look rough, could be the pic? The other is the die. The center part seems to be sitting high. I assume this is part of the decapping stem. But there also appears to be a threaded adjustment stem. It would be interesting to see the parts of the die separated in a pic. Could the center part be making contact with the end of the case?

Frank

 

[PigButtons]

Do you chamfer the case mouth first?

 

[CZSandW]

Do you chamfer the case mouth first?

No I don’t chamfer first. If you recommend I will add it to my routine.

 

[CZSandW]

Two things caught my attention. The end of the case mouths look rough, could be the pic? The other is the die. The center part seems to be sitting high. I assume this is part of the decapping stem. But there also appears to be a threaded adjustment stem. It would be interesting to see the parts of the die separated in a pic. Could the center part be making contact with the end of the case?

Frank

The center part of the die is the threaded rod for decapping. It doesn’t touch the case, the pin on the end pokes the spent primer out. The die was sent back th Hornady, they checked it out said it was okay, polished the titanium nitride sizing ring insert and returned to me.

 

[CZSandW]

That is not normal, I have never had this with any dies. That is a lot of brass shavings.

Yep, a lot of shavings. And thus my concern it might be wearing the cases, although I do not see where any brass has been removed from the cases, even with 10X magnification

 

[mousegunner]

You're taking off whatever burrs are on the case mouth when you size but that seems like a lot. I don't deburr pistol brass as I haven't needed to. Are you trimming the brass at all and leaving burrs?

 

[JMayo]

I'm thinking Belling is stretching the very tiny edge of case mouth then closing it back up is breaking it off as it comes down/out
Go a bit less bell on it and see.

 

[mousegunner]

I'm thinking Belling is stretching the very tiny edge of case mouth then closing it back up is breaking it off as it comes down/out
Go a bit less bell on it and see.

This is on sizing not expanding and crimping.

This has to be happening at the sizing insert, have you tried other brass as well?

Also make sure the case goes straight into the die.

 

[PigButtons]

Easy way to check for any Burr would be to gently wipe the case mouth with a cotton swab and see if it catches any fibers. You say it happens with used cases too. Is it more, less, or the same amount as with the new ones?

I chamfer all case mouths inside and out because I find there's less chance of brass transfer to the die which can lead to scratches on the case.

 

[piie]

More detailed /zoomed images of entire case could help. I’d like to see how the cases look right at the base by the rim; only time I’ve ever experienced shaving of brass was on my 40S&W before I started using carbide dies- normal dies shaved off brass at the Glock bulge near base of case… perhaps your die is set too far down? Anyway, please try to post more images.

Also, you're 100% sure the brass was not perhaps accidentally belled before you resized?

If you have some more brass that has not gone through the sizing step, clean the die and press and then see if you can detect where the shaving happens by slowly partially sizing just the top part of the brass, retract and inspect.

 

[CZSandW]

You're taking off whatever burrs are on the case mouth when you size but that seems like a lot. I don't deburr pistol brass as I haven't needed to. Are you trimming the brass at all and leaving burrs?

No, I haven’t needed to trim because the case lengths are in spec and/or the brass is new

 

[CZSandW]

More detailed /zoomed images of entire case could help. I’d like to see how the cases look right at the base by the rim; only time I’ve ever experienced shaving of brass was on my 40S&W before I started using carbide dies- normal dies shaved off brass at the Glock bulge near base of case… perhaps your die is set too far down? Anyway, please try to post more images.

Also, you're 100% sure the brass was not perhaps accidentally belled before you resized?

If you have some more brass that has not gone through the sizing step, clean the die and press and then see if you can detect where the shaving happens by slowly partially sizing just the top part of the brass, retract and inspect.

The cases havent been belled. That’s a good idea to experiment and partially size, retract and inspect, I will try that in a couple of days.

 

[CZSandW]

Easy way to check for any Burr would be to gently wipe the case mouth with a cotton swab and see if it catches any fibers. You say it happens with used cases too. Is it more, less, or the same amount as with the new ones?

I chamfer all case mouths inside and out because I find there's less chance of brass transfer to the die which can lead to scratches on the case.

The amount of shavings is the same with new or used cases. The case mouths seem smooth, I’ll try the cotton swab method to check. If it continues I’ll try a light chamfer inside and out.

 

[CZSandW]

This is on sizing not expanding and crimping.

This has to be happening at the sizing insert, have you tried other brass as well?

Also make sure the case goes straight into the die.

Correct, cases are not belled at this step.
I’ve tried:
New Remington brass
New Starline brass
used remington
used federal
no lube (Hornady says none needed on titanium nitride die)
with lube, Hornady unique