30 Carbine Brass Problem

[dredd]

Is this a Brass or Rifle Problem?

This is once fired Privi Brass. (Fired from my rifle)
It has only been cleaned & sized.
I found three pieces like this out of 100.
I had reloaded & fired 20 rounds developing my load.

I went to reload the rest of the Brass and found this.
I'm going to call it a Crack.
You can definitely hang a finger nail on it when you drag it across the area.
It is not visible on the inside of the case.

The Rifle was made by Williams Gun Site back in the 60's.
It is in great shape (visibly) and functions great.
No feed or extraction issues.

So.... What are your thoughts?
Toss the Brass?
Load and Shoot the rest of the Brass?
Dig deeper into the Rifle?

Thanks for giving this a look.

 

[USSR]

Looks like it's just where your resizing die stopped resizing. Personally I would load it, keep it separate from your other brass, shoot it, then see what it looks like coming out of your rifle before resizing again.

Don

 

[Reloadron]

They look normal to me, mine look that way. Per Don, it is just a line where the sizing die stops. Here is an example of some of mine run through a RCBS sizing die.

Ron

 

[Rule3]

Also, The 30 carbine is not a "straight wall" case

http://www.saami.org/pubresources/cc_drawings/Rifle/30 Carbine.pdf

Also they must be checked for OAL as they will need trimming, they headspace off the mouth.

 

[dredd]

These three have a tear / crack.

It does look like it happened during the sizing process now that you mention it.

I'll toss these and keep an eye on the others.

I appreciate your input.

 

[dredd]

Rule3,

10-4 on both points.
I have researched & learned a TON on this Forum.
Even with carbide dies, those silly cases still need lube.
No fun hand trimming them either.
I'm used to my WFT's.

Thank you for posting up.

 

[greyling22]

Yep. Lube is a must. About the only thing I can find a use for the spray on lubes for is to lube 9 and 30 carb. And I agree with USSR. Looks like where the sizing die stopped to me..

 

[hdwhit]

Comparing the OP's photograph with that posted by Reloadron, it is clear the line on the OP's brass is higher than the point where the sizing die stops.

Further, the OP says he can hang a fingernail on the "line" in the photograph. The discoloration left by a sizing dies does not cause such a sharp relief.

Tentative conclusion must be that this is not discoloration of the case at the point where the sizing die stopped.

dredd, can you do the "paperclip test" (i.e. straighten a paperclip and bend about 1/8 inch at the tip to use as a feeler; it would be best to sharpen the tip with a file if possible) and use it to check whether the "crack" can be felt inside the case even if it is not visible?

When you have done that, you take the paperclip tester and feel around the inside of the chamber for any discontinuities that might have allowed the brass to displace as it did?

The fact the "crack" is about the same size and at the same location on each case makes me wonder if there is an area inside the chamber where the brass is not being supported. If the chamber has good integrity and only a few cases are demonstrating this failure, then it would be time to look at the brass. It may be the brass was weakened at this point during manufacture and failed in shear upon firing.

Also, if you have calipers or a micrometer, it might be informative to measure the diameter of the case at the web as well as at the "crack" (both diameter at the crack and then diameter of the case with the micrometer turned 90 degrees) and compare it to SAAMI dimension for 30 M1 Carbine.

I would toss any case demonstrating such a "crack" because even if it can be reduced by resizing since the brass has yielded at this point and would be susceptible to catastrophic failure in the future. The likelihood that the chamber would not be able to contain such a failure it is small, but the consequences are dire enough it's not worth a few cases in my book. I would check the remaining cases carefully looking for any sign of a similar, albeit smaller, "crack" in the same location. I would reload any cases that passed a careful inspection (inside and out) and check them carefully for similar failures after second firing.

Please let us know what you discover.

 

[dredd]

No indication of internal crack using a sharpened pick to feel around.

Using Mitutoyo Mic's, everything was within a few 10'ths (.0001) at the "crack" and rotated 90 deg. (.354+)
Same with checking .3548 SAAMI Dia. location which seems to be right behind the crack.
As you know, it is a bit tough getting consistent readings in a tapered area, but I think I'm pretty darn close.

I agree 100% on tossing these 3 cases.
Not worth even dealing with. Too much on the line for something so inexpensive.

All of the other cases look fine.

The other 20 that were reloaded and fired look good as well.

I will do my best to get a good look at the rifles chamber.

If I get any more of these failures after I determine the rifle is good, I think I'll toss all of them and buy something else to load with.

Thanks for the help.
Let me know if you think of anything else.

 

[rcmodel]

Looks like a sizing line to me.

(Die has a abrupt edge instead of being rounded slightly like it should be.)

Is the line there after firing but before sizing??

rc

 

[Walkalong]

Looks like a sizing line to me.

(Die has a abrupt edge instead of being rounded slightly like it should be.)

Certainly what it looks like.

 

[dredd]

RC,

I have 20 cases that have been fired after reloading them one time.
I just wiped them down.

There are several with obvious lines / rings all of the way around.
A few with faint lines and some with no lines at all.

The cleaned and prepped brass is hard to distinguish.
I tumble them in pins after sizing them to make them real purty. LOL

But... you can see by the light bouncing off of them that there are cases with more of an abrupt transition in the same area.

It is looking like the brass is inconsistent with the way it responded to being sized.
Some of it looks like it didn't "flow" nice & easy.
All cases were well lubed with the Hornady Unique Goop.

 

[dredd]

Okay... Here's where I am at...

The Rifle Chamber looks great and feels as slick a Owl Snot.
(Just how slick is Owl Snot anyways?)

I don't think the cases that I reloaded and fired are telling much of a story.
I think they probably looked that way from the sizing before they went pow the second time around.

I have more factory Privi and some Remington that I haven't shot yet.
I will shoot a bunch of that, then give everything a real hard look all of the way through processing.

I appreciate all of y'alls help.
Please let me know if you think of anything else or something I am missing.

Dredd

 

[rcmodel]

Measure the new ammo and get an idea of the size in that area before firing the first time, (by headspamp)

It may be the Privi brass is bigger to start with, so the sizing die is leaving more mark on them.

It could also be your sizing die.

What brand is the die??

rc

 

[dredd]

It is a LEE Die.

I will be sure to measure the Privi & Remington before & after firing.

I would love to rule out the rifle.
I really like it.
I have wanted a 30 Carbine for the longest time.

 

[dredd]

The unfired new Privi is at .3505
The Remington is at .3511

Post firing of reloads on hand:
Privi is at .3572
Remington is at .3580

 

[rcmodel]

Still think your sizing die has a sharp unfinished edge on it.

It could also be undersize, which makes the ring more noticeable.

As for it being so high up the case.

Make sure the sizing die is screwed down tight against the shell holder with the ram up.

It doesn't appear to be now.

rc

 

[dredd]

I believe the die was adjusted correctly, but I will definitely check it again.

I have had good luck we Lee so far, but there is always something that comes off of the line that isn't correct no matter who the mfr is.

As mentioned before, I will go through the next round with a fine tooth comb.

I just may need to get a different sizing die.

Thank you for your time & advice.

I will post up once I get a chance to do this all over again.

Dredd

 

[zeke]

.006 in is considerable difference in brass. It appears the smaller dia brass is expanding more, but the die appears to be made for the fuller size brass, and not sizing the smaller dia brass down close to it's original dia. That would leave a very noticeable step between the unsized and resized portion.

This would also mean the smaller dia brass is expanding more than normal, maybe stressed more.