9mm Case Head Separation

Picture looks like 10% of the once fired 10mm brass I resize. I can only guess it's due to the gun it was fired from but sounds like that wouldn't happen with how you control brass
 
jmorris said:
That is the point of using case gauges vs barrels, to check the portion that the barrel cannot but might hang up on the breech face.

View attachment 1187206

Also, why roll and push through sizers exist, to size the part of the case that is untouched by the normal sizing process.

View attachment 1187207
Click to expand...
I use gauges twice with each round—a case gauge after I size and a cartridge gauge for all completed rounds. But, since I know my barrels vis-a-vis gauges, I only use barrels occasionally/randomly, or when something tells me “that’s odd”, or always when I first use a new bullet or maybe old bullet but new brass combo.

And, no, I’m not buying a roll sizer:)
 
Last edited:
CQB45ACP said:
I use gauges twice with each round—a case gauge after I size and a cartridge gauge for all completed rounds. But, since I know my barrels vis-a-vis gauges, I only use barrels occasionally/randomly, or when something tells me “that’s odd”, or always when I first use a new bullet or maybe old bullet but new brass combo.

And, no, I’m not buying a roll sizer:)
Click to expand...
I’m not buying one either but I sure could put one to use. A lot of the 9/40/45 I have was given to me by friends who shoot at clubs or on public ranges. It’s not just mixed headstamp, it’s a mixed bag of “stuff.” A roll sizer and 10gal wet tumbler would make quick work of it.

But then it would be work and this is my hobby; a way to avoid work. 😉
 
GeoDudeFlorida said:
I’m not buying one either but I sure could put one to use. A lot of the 9/40/45 I have was given to me by friends who shoot at clubs or on public ranges. It’s not just mixed headstamp, it’s a mixed bag of “stuff.” A roll sizer and 10gal wet tumbler would make quick work of it.

But then it would be work and this is my hobby; a way to avoid work. 😉
Click to expand...
Happy NewYear BTW

I get it. BUT, if you ever want someone else to do the hobby/work for you, you could try this guy (Austin)—I bought processed from him several times when I was still accumulating brass and was naive enough to think I had to buy it.

He sells or, if you prefer, processes yours including roll sizing.

Was always willing to anonymize my packages so they didn’t look nor sound like brass or anything else firearms related.

Anyway, haven’t met Austin face-to-face but have spoken to him on the phone. To the extent I trust any stranger, I trust him.

blueridgebrass.com

Blue Ridge Brass, LLC - Home

Reloading | handloading Supplies | Once fired Brass | Wholesale Reloading Brass | Brass Processing | 223 brass | 9mm bulk | 300 blackout
blueridgebrass.com blueridgebrass.com

IMG_0007.jpeg
 
I agree with edwardware, this isn't a problem.
All the picture shows is where the sizing die stopped.
No problem, all my 9mm brass looks the same and some of it has been fired so many times the headstamp is unreadable.
 
bihj said:
I agree with edwardware, this isn't a problem.
All the picture shows is where the sizing die stopped.
No problem, all my 9mm brass looks the same and some of it has been fired so many times the headstamp is unreadable.
Click to expand...
No actually as I said there is a complete crack about one third of circumference. The picture makes it appear as though it’s just a mark.

Post 37 clarifies
 
CQB45ACP said:
No actually as I said there is a complete crack about one third of circumference. The picture makes it appear as though it’s just a mark.

Post 37 clarifies
Click to expand...
I'm not sure I'd "blame" anything or change any process. Experience tells me changing a working process is a good formula for introducing error. I always proceed carefully and with great though before changing my reloading processes. It takes planning.

On the other hand, if you don't trust the current process anymore, then going back to a known-working process - with some careful planning - is essential. A lot of what we do as handloaders is based on trusting our processes. The rest is planning, documentation, QC, and movement memory.
 
GeoDudeFlorida said:
I'm not sure I'd "blame" anything or change any process. Experience tells me changing a working process is a good formula for introducing error. I always proceed carefully and with great though before changing my reloading processes. It takes planning.

On the other hand, if you don't trust the current process anymore, then going back to a known-working process - with some careful planning - is essential. A lot of what we do as handloaders is based on trusting our processes. The rest is planning, documentation, QC, and movement memory.
Click to expand...
Yes I agree.

Although I always have examined brass closely throughout the process, I am no longer going to assume an apparent rub mark from a sizer is ONLY a rub mark and not also a crack. At first, that crack was really hard to see even holding the case in my hand.

Given this batch of brass is a little long in the tooth, I may go back to a standard sizer to eliminate an obvious source of rub marks. Or is that a source of obvious rub marks?
 
CQB45ACP said:
actually as I said there is a complete crack about one third of circumference. The picture makes it appear as though it’s just a mark.
Click to expand...
Crap happens. Sometimes cases just crack or split.

My guess is the sizer is damaging the case right there from being too tight/sharp at the bottom of the carbide ring.

Not sizing quite as far down might help, but when it happened to me, on two different occasions, I bought better made dies.
 
Walkalong said:
Crap happens. Sometimes cases just crack or split.

My guess is the sizer is damaging the case right there from being too tight/sharp at the bottom of the carbide ring.

Not sizing quite as far down might help, but when it happened to me, on two different occasions, I bought better made dies.
Click to expand...
Yes it does I just don’t want to unnecessarily contribute to it.

Funny I started out seeing how long cases would last and now that I may be finding out it’s not forever, I don’t like it.
 
Lee sizer with a long tapered carbide insert.

Redding sizer with two carbide rings.

I have read the newer RCBS sizers have a long tapered carbide insert, but I haven't seen one.

Some of my 9MM cases used to look like that until I switched to the Lee.
 
Walkalong said:
Using the Lee sizer.
View attachment 1187323
Click to expand...
Nice photo.

Before I used the Lee undersized, I had always used their standard and mine looked like this. (The cartridges not photos.) And I was a happy camper. No expanding/no flare either.

But I seemed to be getting some pretty easy seating and setback concerned me. That drove me to the undersized die.

When I say easy, I mean I couldn’t feel resistance as the bullet was seated. Not some, none. Again, in a non-expanded case I didn’t like that at all.

Now part of that was likely the Redding competition seater keeping the bullet straight. And probably the slickness of the .355” Extreme plated bullets contributed.

I also wouldn’t be surprised if some of the bullets were a bit undersized. Not sure about the latter but they certainly had an inconsistent ogive as seating depth wasn’t as consistent as it should be.

Ironically perhaps, I was about to be “forced” to go back to the standard sizing and/or expanding.

I just bought some new Berry’s .356” 115gr RN and not only are they larger, they’re apparently less slick with maybe thinner plating. Seem to have same degree of beveling. Try as I might, they would not seat without scraping off the plating even in a chamfered case. Got a few to work, but ruined 8 bullets experimenting. (And I’ve come to be really good at holding a bullet straight without pinching my fingers.)

Don’t see the point in under sizing then expanding back to accept a bullet. Why not start larger, I’m thinking.

Thanks for engaging and lending your expertise.
 
When brass is fired, resized, expanded, flared, the material has to flow somewhere. The more it is worked the more flow takes place. So if you are using an undersized sizing die, it follows that the material is flowing more. One of the side effects may be thinner case walls, which would contribute to less grip on the bullet. Perhaps a cascading effect on your process.

Along with work hardening, these things can shorten case life.
 
pa4445 said:
When brass is fired, resized, expanded, flared, the material has to flow somewhere. The more it is worked the more flow takes place. So if you are using an undersized sizing die, it follows that the material is flowing more. One of the side effects may be thinner case walls, which would contribute to less grip on the bullet. Perhaps a cascading effect on your process.

Along with work hardening, these things can shorten case life.
Click to expand...
Makes perfect sense to me.
 
Okay, now that y’all have my attention about Redding dual carbide ring sizing die, I see Midway and Opticsplanet both have it listed as discontinued :( and I can’t find it on Redding’s website. Am I not looking in the right places or is it really kaput?
 
You must log in or register to reply here.

Similar threads

Nature Boy
  • Locked
Case head separation with a lesson learned
2
Replies
25
Views
1K
Barman54
Barman54
F
  • Locked
Incipient case head separation?
Replies
1
Views
428
GP100man
G
G
  • Locked
Sizing marks vs. case head separation
Replies
5
Views
2K
goon
G
G
  • Locked
Case head separations. Are they a big deal?
2
Replies
36
Views
2K
Fisherdave10
F
coloradokevin
  • Locked
Incipient Case Head Separation
2
Replies
34
Views
4K
RentaCop
R
Back
Top