Anyone noticed little "tears" in the brass of RMC cases after firing?

[cpileri]

So i fired these one time, with standard pressure, though heavy, loads; and after cleaning them i noticed little longitudinal rifts or tears in the brass.
They are definitely a cleft on the surface, but not very deep; and nothing appears inside the case.

Also, they are along the length of the hull, not circumferantial like a case seperation would be. The case is not otherwise bulged nor expanded over sized, and I have not attempted to re-size it in any way.

Just bought it, and fired it once in the USH.

I'll try to post a picture.

Do you think this affects the safe use of the brass? i expected this robust brass hull to last longer, be stronger.

Since there are no internal stress marks, do you think i can still use it for lighter loads?

Has this happened to anyone else?

C-

I realize that the answers is probably "no way to tell from here", but i am reaching out!

84490

[cpileri]

84491

[billyb]

Are you picking up impressions of tooling marks from your chamber? I have I seen this in heavy load 44 mag brass. Bill

[BK7saum]

It does look like something in your chamber is causing dents/marks in your brass.

[cpileri]

I guess it could be the chamber, I'll check. But these look more like someone took a tiny pick and dug a mini-crevasse into the brass. and none of the other 6 brass cases nor any of the plastic hulls seem to have taken such an indentation.

i suppose it could have been somethign that was just dirtying up the chamber, and not a permanent part of the chamber like a tool mark.

I was just wondering if any other RMC brass users had anything similar happen.

C-

[williamwaco]

I have never seen anything like that but I would NOT reuse those cases.

[Doc Highwall]

Did you size them before you loaded them? I have seen marks like that from a sizing die that had some brass that was "cold welded" from not using enough case lube and it will gall the brass like that, and case neck expanders with brass buildup do the same thing to the insides of case necks.

[cpileri]

No, sir, no resizing at all.
I might try to send them back to rmc and see what they say.
C-

[Driver man]

Looks to me like a foreign object in the chamber. I would not use that brass for anything.

[Horace]

cpileri.
What cartridge?
What is a"USH"? "Just bought it, and fired it once in the USH."

Horace

[tomme boy]

H&R Ultra Slug Hunter = USH

[hubel458]

Have you fired other RMC brass in that chamber, that did not
make marks like that. Ed

[cpileri]

yes, sir. One other ctg has a small but similar mark, the others are pristine.
C-

[Horace]

Thanks tomme boy.

Horace

[hubel458]

You got a scope rail on the gun.Ed

[cpileri]

Yes, Sir, a scope rail.
I need to check that chamber.
Mr. hubel, you've seen it, the USh you reamed for me.

[cpileri]

Here are a couple pics of the chamber, badly done, but look very smooth to me; nothing obvious.
84560

[cpileri]

and
84561

[cpileri]

And now that i checked the brass, after drying all night; seems all but one(*) has picked up some sort fo longitudinal line. the one on left is the ccase i first showed, with by far the deepest rift. The others vary from a smaller rift to barely a cosmetic flaw.
84562

(*) interestingly, the one that remained pristine -not shown- was one of the 56gr Steel Hubel 440gr Sabot loads, one of the hottest.

[cpileri]

it could be the gun, load, etc- but if there is a defect in the bar stock; and it is reasonable to assume they were all machined from the same rod during a machining run, maybe its the brass?
C-

[w5pv]

Take some persian bluing and see if you can find a high spot in the chamber.Use a very light amount.

[cpileri]

never done persian blueing. can you describe the procedure a little.
C-

[hubel458]

It could be something in the chamber that caused that.
It looked smooth to me when done. If there is a hump or rough
spot you can smooth up with brake cylinder hone. Or I can.

OR THE LOAD WAS TO LIGHT for the thick case and case didn't expand
on firing to grip chamber walls fast enough, and gases blow back by
the side of the case leaving residue. What sabot/slug and
powder and amount was used on the scuffed ones.Ed

[cpileri]

it is smooth, I posted the pics; but to my eye when looking its very slick. A feeler guage (dental pick) cant find any defect in the chamber.

Of the 5 cases shown, 2 were fired w 56gr A.Steel and a Hubel sabot w 440gr slug, plus wadding; and the other 3 were fired w 54gr IMR 4227 and a 1043gr slug, plus wading. No light loads.

C-

[hubel458]

In that brass case we have used up to 70gr steel with
light slugs/sabots. By light I mean 500gr or less.
For light sabot loads I use 105 gr 4759 in 3.5" brass case.

With IMR4227, IMR4759 and VV110(all close to same speed)in 12ga, must use a
a minimum starting load to get proper, no squib, no erratic ignition, loads.
That is 70 gr. Now I know that is a problem recoil wise with ultra heavy
slugs, but barrel will handle it ok. Have you got the gun weighted.

That is why I discourage the super heavy slugs in break actions as it takes
a little doing to get weight up. Like drilling out some big holes in the butt and fill with lead.

Also I quit using 4227 and only use 4759
at that powder speed, 4227 burned to erratic. Also when I had a load smudge
the outside of a case, while developing loads I cleaned bore so that if
there was unburnt grains they wouldn't get blown back between chamber and case on next load if it did the same.

Powder grains can scratch half hard brass. Now these
cases are they same ones you just sent me to size for you.
They just got here. Ed

[cpileri]

No. Same order from rmc, but he ones i sent you are pristine as bought.
C-


In that brass case we have used up to 70gr steel with
light slugs/sabots. By light I mean 500gr or less.
For light sabot loads I use 105 gr 4759 in 3.5" brass case.

With IMR4227, IMR4759 and VV110(all close to same speed)in 12ga, must use a
a minimum starting load to get proper, no squib, no erratic ignition, loads.
That is 70 gr. Now I know that is a problem recoil wise with ultra heavy
slugs, but barrel will handle it ok. Have you got the gun weighted.

That is why I discourage the super heavy slugs in break actions as it takes
a little doing to get weight up. Like drilling out some big holes in the butt and fill with lead.

Also I quit using 4227 and only use 4759
at that powder speed, 4227 burned to erratic. Also when I had a load smudge
the outside of a case, while developing loads I cleaned bore so that if
there was unburnt grains they wouldn't get blown back between chamber and case on next load if it did the same.

Powder grains can scratch half hard brass. Now these
cases are they same ones you just sent me to size for you.
They just got here. Ed

[hubel458]

Yes these are nice and smooth. If those cases are just scratched
by hard burnt powder grains they will resize and work ok.
I'll check them over if you want and size them test them with top loads.
Size them and send back.I have heavy guns with thumbhole stocks. I've never had RMC case split and have used
200gr RE17 in 3.5" case with light sabot slugs in
my heavy NEF.ED

[cpileri]

Sure, I'll send them, if only to know wether or not they are safe to use.
I also have an email out to RMC, so will see what they say as well.
Thanks!
C-

[cpileri]

Just a question: if this is gas cutting, wouldnt i see a divet at the case (hull) mouth? these lines all seem to start after/beneath the case mouth.
C-

[hubel458]

I don't know. Maybe when we look at them we
can figure it out.Ed

[Doc Highwall]

How about taking a loaded case that has no gouge marks on it and mark it with a magic marker and place the mark at the 12 o'clock position of the chamber and fire it. If it comes out of the chamber with a mark at least you will have an idea where to look in the chamber for what is causing it.

[cpileri]

Doc highwall, that is a good idea.
RMC says to send them back and they'll check them. After that, if i still have the cases, i'll let Mr. Hubel check them and go from there.
I'll fire a pristine one, though w a mark and see what happens.
C-

[cpileri]

So I got some results back from Mr. Hubel's analysis: appears to be cracks! He considers NONE of these safe to fire.

Either a defect in the base brass bar stock or else the alloy/temper was not compatible/successful for whatever reason.

In any case, i am sending them all back to RMC to let them check their handiwork. Not anticipating any problems w them, since even Ed says he has NEVER seen anythign like this in turned brass cases; even in his heavy loads and use.

SO it might be some time before I get these up and runnign again, but i am sure I will and of course will post any results.

C-

[hubel458]

I've fired 30,000 psi loads in 12ga and 4 bore, and 20 ga RMC
cases and never anything like that. Got 2 big 4bores been fired 15-20
times each, and no cracks or splits. Got to be bad bar stock, IE
acts like it is too brittle, I filed one spot halfway down into the thickness
of the brass and could still see a crack.

Maybe it is easier in my old age to get long plastic cases for pennies
and shoot them as hot as whatever they can stand.Still
a lot of power, Ed

[cpileri]

Update:
results of new RMC cases fired in same gun here:
http://castboolits.gunloads.com/showthread.php?239508-Test-6-of-Greg-Turbo-Tommygirl-FH-SuperBlazing-Dixie-Hawglips-Hogtamer-bikerbeans-ins



So I got some results back from Mr. Hubel's analysis: appears to be cracks! He considers NONE of these safe to fire.

Either a defect in the base brass bar stock or else the alloy/temper was not compatible/successful for whatever reason.

In any case, i am sending them all back to RMC to let them check their handiwork. Not anticipating any problems w them, since even Ed says he has NEVER seen anythign like this in turned brass cases; even in his heavy loads and use.

SO it might be some time before I get these up and runnign again, but i am sure I will and of course will post any results.

C-

[cpileri]

Follow up:
the replacement RMC hulls fired these same loads w no problems. no cracks, tears, etc- perfect and performed as expected.
C-

[opos]

I know lots of folks have and still use and swear by RP brasss....I hand sort and pick out the RP brass and crimp it and dump it in the can...I've had really bad luck with inconstant wall thickness and expanding using RP brass...have measured much of it when the case would not hold a projectile..thumb pressure tight only...no problems or issues with any other brass at all...I processed several "mixed" lots of RP, Starline, Federal American Eagle and several other "off shoot brands...this was done with my dies in 38/357 ....I also used a buddies dies after I began to have issues and had exactly the same results...can't be a die out of spec...it's the brass...Again, I have never had a batch run where a particular number of loaded shells had the projectiles seated so loose that they could simply be pushed into the cases with thumb pressure...measuring before seating a projectile and after sizing and belling gave the same result...the RP cases were less apt to grip the projectile and in measuring the brass at the neck was several thousanths thinner...Your mileage may vary...and it's only my 2 cents...I simply will not use RP brass for anything any more.

PS...all of the cases were my personal fired cases from new ammunition...I do not have the exact record but the cases were probably no fired more than 3 times and many were once fired...none were "hot loaded"..the factory load would have been the hottest load....none were nickel..all were brass...no noticed issues with cracks or splits.

[hubel458]

Quote-''replacement RMC hulls fired these same loads with no problems''

That is great news, Makes me very happy as I have others that want

to get cases from Them...ED

[birddog]

Buy a 12 ga chamber hone and polish the chamber, tell us how that works
Charlie