What is causing this to my brass!!!!!

[Mark611]

 

[piie]

Indentations? If so, probably the presence of a fluid while sizing / firing? Sorry, you give basically no additional info - when do you see this - after sizing, after firing?

 

[Mark611]

This brass is new once fired Starline, shot out of the box, I basically annealed and checked the cases in a Sheridan slotted case gage, expanded the necks loaded them and fired them from my Zastava M77PAP 308win, I shot about 100rnds and half of the brass came out with these cracks after they were fired, this is not from sizing,

 

[M-61]

these cracks

Cracks or scratches? Huge difference.
No clue what a slotted Sheridan case gauge is or what it’s supposed to indicate.
If these are marks on the case the one on the right is in an area that would be of concern as it appears roughly in an area that is where the case separates.
Half the cases, 50 !, came out like this?

 

[1shot]

A couple of questions for the OP.
1. Out of the roughly 50 cases, are the marks similar in size, shape and location?
2. Have you determined if they are scratches or cracks?
Please let us know so that we can better help you.

Lloyd

 

[Mark611]

Lloyd, most all the cases that I have pix of look the same as far these marks, in the same places on all the cases, to me they look stress fractures, I took a piece of 4/0 steel wool and tried to polish out these marks, and there still there! rubbing my thumb nail across these marks I do not feel them?

 

[1shot]

Lloyd, most all the cases that I have pix of look the same as far these marks, in the same places on all the cases, to me they look stress fractures, I took a piece of 4/0 steel wool and tried to polish out these marks, and there still there! rubbing my thumb nail across these marks I do not feel them?

Thanks for the quick response.
My first thought is an oversized chamber, with faulty brass coming in a close 2nd.
Have you fired another brand of brass in that rifle?

 

[M-61]

Gee, I thought I asked those exact questions in post 4?

 

[Mark611]

No, I've had this rifle for a few yrs now and just started shooting it a few mons ago, just started to re process the hand loads I loaded for it, and this is what I ran across with the brass!

 

[Mark611]

308 WIN Ammunition Gauge

Choose between SLOTTED or NON-SLOTTED. AMMUNITION GAUGES are uniquely designed to check loaded ammunition, giving you the ability to check your factory ammunition or reloads against a spec chamber. The gauge is machined to the SAAMI minimum chamber spec for the 308 WIN caliber. This…

sheridanengineering.com

 

[dvraa]

View attachment 1643930

I had the same problem with some RCBS 45 Basic brass. I called them and they said they had a bad batch. They sent me replacement brass free.

 

[Mark611]

That's what I'm trying to find out! all my hand loads are not at max loads, depending on powder choice I'm 2 to 4gns under a max load! with this brass and rifle, for example my largest powder charges were 44gns of Shooters World Match rifle under a 147 or 150gn pill, max load is 48+gn weight with these bullet weights, same bullet weights with 45gns of A2520 max is 47.1 I believe, IMO this is something very strange and something I have not experienced in my 35yrs of reloading,

 

[Wild Bill IV]

It looks like bad extrusions from the factory!!! Most likely, a dirty die or a chipped punch!! Or, dinging in the staging for the next formation station causing roll over or folding!! The more I look at the pixs, it is roll over! I've seen this in metal stock in plates, sheets, flats, and rounds!!! SEND THEM BACK!!!

 

[6.5 forever]

Bad brass.

 

[coldboreshot]

Agreed^^^^^^^^

 

[243winxb]

This brass is new once fired Starline, shot out of the box

Chamfer & deburr brass before loading.

 

[bpd459]

View attachment 1643930

Are you sizing right after annealing? The scratches on your case necks is caused by an oxide that is a result of the annealing. It is harder than carbide. I run my annealed brass for 10-15min in the tumbler to clean it off. Some brass compounds have it and some don’t. This info is from a family friend with a doctorate in metallurgy.

 

[358WCF]

Looks like impressions from debris in the chamber to me. I had a sliver of brass shaved from, I believe, the belt stuck in my 358 Norma a while back. Ruined 1/2 a box of brass after the marks turned into cracks during later firings. Bore scope & a small pick were needed to remove it.

 

[divingin]

What does the brass look like coming out of the chamber? What does the new out of the box/bag brass look like? That stuff looks pretty beat up for a single loading. Are you sizing the new brass before the first loading? Are you annealing the new stuff (I suspect it's annealed before leaving the factory), or annealing after the first firing? You're using the case gauge, but do you know that your chamber is a close match to the gauge?

Neck scratching:
Either brass chips or annealing oxides damaging the brass while sizing. If it's brass, it's likely embedded in the sizing die now, and will need to be cleaned (I use 600 or 800 grit wet/dry sandpaper with oil, wrap the tip of a small bore mop, and spin it in the neck part of the die.) New brass should be chamfered and deburred, and it's a good idea to spin it with a scotchbrite pad or steel wool to remove any errant chips.
For the annealing, hit the annealed neck with a bit of 0000 steel wool before sizing. Make sure you're lubing adequately.

Body marks:
Check your headspace to ensure you're not overly stretching your brass. Scotch tape on the casehead will give you a rough idea of how short your case is (vs chamber length) - shouldn't be more than 2 layers. I usually load my first firing on new brass with the bullet jammed to try and minimize case body stretch.

Also, make sure your chamber is clean. Some of those marks look like pet hair or lint or similar in the chamber when firing.

 

[Mark611]

Thanks guys! why would I not see this in unfired cases? I've been going through the box of brass Looking at the rest of the cases, I have not ran across any so far unfired cases that look like this, but I have not looked at all of them, in your opinions, the anomalies I'm seeing? what could happen to the brass if I were to load them again?