blackened brass

jjcbuck · March 8, 2012, 03:32 PM

What is the cause of new hand loaded brass showing black residue half way down the brass on both 9mm and .45 ACP when fired.

DWFan · March 8, 2012, 03:34 PM

This is usually a sign of low pressure and inadequate seal of the case to the chamber wall.

jjcbuck · March 8, 2012, 03:36 PM

Could this be caused by too much of a crimp? I know 9mm and .45 ACP must not be crimped too much.

DWFan · March 8, 2012, 03:44 PM

Since these are taper-crimp rounds, I guess it's possible; but I would think that too much of a crimp would drive pressures up, not down. I don't load either of these so hopefully someone experienced will chime in.

bossman · March 8, 2012, 03:58 PM

Quote:

Originally Posted by DWFan

This is usually a sign of low pressure and inadequate seal of the case to the chamber wall.

+1 That will do it.

markr · March 8, 2012, 04:09 PM

+2 on the low pressure.

howlnmad · March 8, 2012, 04:11 PM

+3 on the low pressure. Case isn't expanding and filling out the chamber allowing gasses to blow by.

F. Guffey · March 8, 2012, 04:29 PM

jjcbuck, I am the fan of the crimp, not a real big problem but there is a limit to the effect a crimp has on pressure, I would suggest reading R. Lee;s book on modern reloading. I do not know how to advise you on your blackened cases. I believe time is a factor, in your opening post you did not list the powder, there are powders that are slow pistol powders, the same powder can be a fast rifle powder. It is not easy to load 9mm pistol ammo for the wife, it was suggested I make her angry, they said making her angry would automatically cause her to hold the pistol tighter, loading her ammo heavier does the same thing.

F. Guffey

markr · March 8, 2012, 04:38 PM

I learned this the first time I loaded 30-06 and worked my loads up starting at the minimum charge. The cases were all black and sooty until the middle to high end of the powder charge range.

zxcvbob · March 8, 2012, 04:51 PM

Are you using Titegroup powder? It is notorious for that, but moreso with straight-sided cases like .38 Special.

jjcbuck · March 8, 2012, 05:07 PM

Thanks for the input. These are not my loads I am inquiring about. I am an RO at a local personal defense league and I noticed this blackening in his 9mm and .45 rounds. He asked me the cause and I did not know. I don't know what powder he is using or the amount. I thought I would pick a few experienced brains before I try to respond to him next week. Thanks again for your input.

jjcbuck

primerman · March 8, 2012, 08:39 PM

Yea, I just ran into that same thing (Again) working on some 9mm loads with Titegroup powder. On my loads it is defiantly to low a charge so I am going to have to bump my load up a little. I've been working a load down from 4.3 grains and made it down to 3.5 grains where the burn mark (What I call it) on the side of the case showed up. Just as information, my Walther PPS and my Springfield EMP did not cycle properly with this charge so I will be bumping up my charge a little on the next batch. I have also noticed these burn marks on cases using other powders with a low charge. Hey, what can I say it happens...

March 8, 2012, 03:32 PM	#1
jjcbuck Member Join Date: March 8, 2012 Location: NY Posts: 18	blackened brass What is the cause of new hand loaded brass showing black residue half way down the brass on both 9mm and .45 ACP when fired.

March 8, 2012, 03:36 PM	#3
jjcbuck Member Join Date: March 8, 2012 Location: NY Posts: 18	blackened brass Could this be caused by too much of a crimp? I know 9mm and .45 ACP must not be crimped too much.

March 8, 2012, 04:09 PM	#6
markr Senior Member Join Date: January 23, 2008 Location: Arsenal of Democracy Posts: 329	+2 on the low pressure. __________________ I like to make beer, bullets, and jerky.....but not at the same time. Washed up 11B1P

March 8, 2012, 04:38 PM	#9
markr Senior Member Join Date: January 23, 2008 Location: Arsenal of Democracy Posts: 329	I learned this the first time I loaded 30-06 and worked my loads up starting at the minimum charge. The cases were all black and sooty until the middle to high end of the powder charge range. __________________ I like to make beer, bullets, and jerky.....but not at the same time. Washed up 11B1P

March 8, 2012, 04:51 PM	#10
zxcvbob Senior Member Join Date: December 20, 2007 Location: S.E. Minnesota Posts: 3,693	Are you using Titegroup powder? It is notorious for that, but moreso with straight-sided cases like .38 Special. __________________ "The only way to stop a bad guy with a gun is with a good guy with a gun"

March 8, 2012, 03:34 PM	#2
DWFan Senior Member Join Date: April 25, 2008 Posts: 206	This is usually a sign of low pressure and inadequate seal of the case to the chamber wall.

March 8, 2012, 03:44 PM	#4
DWFan Senior Member Join Date: April 25, 2008 Posts: 206	Since these are taper-crimp rounds, I guess it's possible; but I would think that too much of a crimp would drive pressures up, not down. I don't load either of these so hopefully someone experienced will chime in.

March 8, 2012, 04:11 PM	#7
howlnmad Senior Member Join Date: April 29, 2009 Location: Harriman Tn Posts: 362	+3 on the low pressure. Case isn't expanding and filling out the chamber allowing gasses to blow by.

March 8, 2012, 04:29 PM	#8
F. Guffey Senior Member Join Date: July 18, 2008 Posts: 1,622	jjcbuck, I am the fan of the crimp, not a real big problem but there is a limit to the effect a crimp has on pressure, I would suggest reading R. Lee;s book on modern reloading. I do not know how to advise you on your blackened cases. I believe time is a factor, in your opening post you did not list the powder, there are powders that are slow pistol powders, the same powder can be a fast rifle powder. It is not easy to load 9mm pistol ammo for the wife, it was suggested I make her angry, they said making her angry would automatically cause her to hold the pistol tighter, loading her ammo heavier does the same thing. F. Guffey

March 8, 2012, 05:07 PM	#11
jjcbuck Member Join Date: March 8, 2012 Location: NY Posts: 18	Thanks for the input. These are not my loads I am inquiring about. I am an RO at a local personal defense league and I noticed this blackening in his 9mm and .45 rounds. He asked me the cause and I did not know. I don't know what powder he is using or the amount. I thought I would pick a few experienced brains before I try to respond to him next week. Thanks again for your input. jjcbuck

March 8, 2012, 08:39 PM	#12
primerman Senior Member Join Date: December 23, 2011 Posts: 124	Yea, I just ran into that same thing (Again) working on some 9mm loads with Titegroup powder. On my loads it is defiantly to low a charge so I am going to have to bump my load up a little. I've been working a load down from 4.3 grains and made it down to 3.5 grains where the burn mark (What I call it) on the side of the case showed up. Just as information, my Walther PPS and my Springfield EMP did not cycle properly with this charge so I will be bumping up my charge a little on the next batch. I have also noticed these burn marks on cases using other powders with a low charge. Hey, what can I say it happens...