Brass marred by rifle

Willkk · November 21, 2014, 12:45 AM

I went to the range today and fired 20 of my first hand loads. These are all starting loads per Lyman manual at standard lengths. When I got home and cleaned these I noticed that 3 of the 20 had this mark:

http://i48.photobucket.com/albums/f2...ithk/brass.jpg

What could cause this? And why on only three? I never even let these touch the bench. Box, to rifle, back to box. Any ideas?

William T. Watts · November 21, 2014, 08:06 AM

I assume a bolt gun, first I would use flitz and a bore mop on the sizing die to be sure there isn't a problem there, then the same bore mop on the chamber spin it up with a drill motor briefly (10-15 seconds). This product will polish the chamber only, If any metal is removed it will be microns, I like this product for polishing because it doesn't change the dimensions of the metal your polishing. I admit what you see on the case does look strange and quite unusual. Do Not Use a Rubbing Compound, those products are too aggressive and will remove metal..William

wogpotter · November 21, 2014, 09:13 AM

I'm guessing a hair of swarf from manufacturing.
Try looking in the die & chamber with a bright light (Mag Lite fiber-optics are great for this). If you ca see it fish it out with a non-marring pic of some kind.(paperclip tip bent to a "V" for example).

cw308 · November 21, 2014, 10:44 AM

I would mark those cases with a marker, clean all the cases, size all the cases again. Check your case measurements, trim all to same length, reload same cases, remark the three cases and see if the problem follows the case. I wouldn't do anything to the die or the chamber except clean for now. 3 out of 20 I would think something in your sizing

jag2 · November 21, 2014, 11:27 AM

Lots of things to try, WTWs suggestions are a good start. I have also used a wadded up piece of 0000 steel wool but use it like a mop. You could put a bit of polish on the wool (I've used Flitz) and also a little oil if I think there may be some rust. Start out with shorter time, maybe 5 to 7 seconds to start. Further down the road if you are still having problems you may need to look at shoulder set back.

**Unclenick** · November 21, 2014, 11:32 AM

If the rifle is a self-loader, it could be the case spinning on ejection and smacking into the frame somewhere. Case lube left on the cases could do it in a bolt gun chamber. A shoulder indented by excess lube during sizing might lead a mark when pressure fire-formed the case back out again.

So, several questions come up:

What is the gun make and model?
Did you inspect resized cases for dents?
Did you clean lube off the cases before shooting them?
How identical is the mark on the other cases? Same size and shape exactly or does its shape or location vary some?

Snyper · November 21, 2014, 12:26 PM

Quote:

3 of the 20 had this mark:

If only 3 had the mark, it was something temporary

I'd suspect a thin shaving of brass in the chamber or die, and the cases were done consecutively

Since it's not on all the fired cases, it's already solved itself

Paul B. · November 21, 2014, 05:02 PM

"If only 3 had the mark, it was something temporary

I'd suspect a thin shaving of brass in the chamber or die, and the cases were done consecutively

Since it's not on all the fired cases, it's already solved itself."

My thoughts exactly.
Paul B.

FrankenMauser · November 21, 2014, 05:16 PM

I'd put the odds at 93-97% for:

It was a sliver of copper that got scraped off of a bullet while seating, and dropped into the chamber upon chambering or extraction. Subsequent cartridges fired in the chamber picked up the impression, until the debris was removed.

Let me guess.... flat base bullets in cases that weren't chamfered?

Longshot4 · November 21, 2014, 08:34 PM

Unclenic seams to be on it as others. It is a unique marking that is similar to what I see when a grain of fine ball powder is clinging to the outside of a case when fired in the chamber. It also reminds me of a case not feeding in to the chamber smoothly and jamming. It is a good thing to always inspect cases as you go through the loading process. Also when the rifle is cleaned it is a good idea to inspect the bore and chamber for that thread form the patch...
I like to check my case holders and boxes to keep them clean from contamination from the loading process... It's a good idea to carefully inspect the case mouth for a nice neat inside chamfer in the inside to guide the bullet and no burr on the out side of the case mouth. You don't want a knife edge on the mouth of the case either. Use your fingers to feel and your eyes for inspection of the cases. Keep the bench clean. I don't like the case shoulders to be damaged so I would toss those cases in a box so I can have them as a learning tool.

November 21, 2014, 12:45 AM	#1
Willkk Member Join Date: November 5, 2014 Posts: 17	Brass marred by rifle I went to the range today and fired 20 of my first hand loads. These are all starting loads per Lyman manual at standard lengths. When I got home and cleaned these I noticed that 3 of the 20 had this mark: http://i48.photobucket.com/albums/f2...ithk/brass.jpg What could cause this? And why on only three? I never even let these touch the bench. Box, to rifle, back to box. Any ideas?

November 21, 2014, 08:06 AM	#2
William T. Watts Senior Member Join Date: January 20, 2010 Location: Central Arkansas Posts: 1,074	I assume a bolt gun, first I would use flitz and a bore mop on the sizing die to be sure there isn't a problem there, then the same bore mop on the chamber spin it up with a drill motor briefly (10-15 seconds). This product will polish the chamber only, If any metal is removed it will be microns, I like this product for polishing because it doesn't change the dimensions of the metal your polishing. I admit what you see on the case does look strange and quite unusual. Do Not Use a Rubbing Compound, those products are too aggressive and will remove metal..William Last edited by William T. Watts; November 21, 2014 at 08:14 AM.

November 21, 2014, 09:13 AM	#3
wogpotter Senior Member Join Date: September 27, 2004 Posts: 4,811	I'm guessing a hair of swarf from manufacturing. Try looking in the die & chamber with a bright light (Mag Lite fiber-optics are great for this). If you ca see it fish it out with a non-marring pic of some kind.(paperclip tip bent to a "V" for example). __________________ Allan Quatermain: “Automatic rifles. Who in God's name has automatic rifles”? Elderly Hunter: “That's dashed unsporting. Probably Belgium.”

November 21, 2014, 11:32 AM	#6
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	If the rifle is a self-loader, it could be the case spinning on ejection and smacking into the frame somewhere. Case lube left on the cases could do it in a bolt gun chamber. A shoulder indented by excess lube during sizing might lead a mark when pressure fire-formed the case back out again. So, several questions come up: What is the gun make and model? Did you inspect resized cases for dents? Did you clean lube off the cases before shooting them? How identical is the mark on the other cases? Same size and shape exactly or does its shape or location vary some? __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

November 21, 2014, 05:02 PM	#8
Paul B. Senior Member Join Date: March 28, 1999 Location: Tucson, AZ Posts: 3,802	"If only 3 had the mark, it was something temporary I'd suspect a thin shaving of brass in the chamber or die, and the cases were done consecutively Since it's not on all the fired cases, it's already solved itself." My thoughts exactly. Paul B. __________________ COMPROMISE IS NOT AN OPTION!

November 21, 2014, 10:44 AM	#4
cw308 Senior Member Join Date: September 2, 2010 Location: Plainview , Long Island NY Posts: 3,863	I would mark those cases with a marker, clean all the cases, size all the cases again. Check your case measurements, trim all to same length, reload same cases, remark the three cases and see if the problem follows the case. I wouldn't do anything to the die or the chamber except clean for now. 3 out of 20 I would think something in your sizing

November 21, 2014, 11:27 AM	#5
jag2 Senior Member Join Date: June 30, 2009 Location: dallas Posts: 773	Lots of things to try, WTWs suggestions are a good start. I have also used a wadded up piece of 0000 steel wool but use it like a mop. You could put a bit of polish on the wool (I've used Flitz) and also a little oil if I think there may be some rust. Start out with shorter time, maybe 5 to 7 seconds to start. Further down the road if you are still having problems you may need to look at shoulder set back.

November 21, 2014, 05:16 PM	#9
FrankenMauser Senior Member Join Date: August 25, 2008 Location: In the valley above the plain Posts: 13,424	I'd put the odds at 93-97% for: It was a sliver of copper that got scraped off of a bullet while seating, and dropped into the chamber upon chambering or extraction. Subsequent cartridges fired in the chamber picked up the impression, until the debris was removed. Let me guess.... flat base bullets in cases that weren't chamfered? __________________ Don't even try it. It's even worse than the internet would lead you to believe.

November 21, 2014, 08:34 PM	#10
Longshot4 Senior Member Join Date: February 22, 2014 Posts: 868	Unclenic seams to be on it as others. It is a unique marking that is similar to what I see when a grain of fine ball powder is clinging to the outside of a case when fired in the chamber. It also reminds me of a case not feeding in to the chamber smoothly and jamming. It is a good thing to always inspect cases as you go through the loading process. Also when the rifle is cleaned it is a good idea to inspect the bore and chamber for that thread form the patch... I like to check my case holders and boxes to keep them clean from contamination from the loading process... It's a good idea to carefully inspect the case mouth for a nice neat inside chamfer in the inside to guide the bullet and no burr on the out side of the case mouth. You don't want a knife edge on the mouth of the case either. Use your fingers to feel and your eyes for inspection of the cases. Keep the bench clean. I don't like the case shoulders to be damaged so I would toss those cases in a box so I can have them as a learning tool. Last edited by Longshot4; November 21, 2014 at 08:40 PM.