carbon on outside of neck

[redneckturkeycaller]

I seem to be getting a lot of carbon on the outside of my necks. Is this caused by a low powder charge. Thanks for all of the help in the past.

 

[fdshuster]

The amount of carbon fouling I see on my case necks is an indication of how much I will also see in the bore, when using my Hawkeye Borescope. Ball powders like WW748, H380, H414, etc. are the worst offenders. VihtaVouri is the cleanest.

If I'm using one of the fouling powders (seldom do) I usually wipe the case necks as they come out of the chamber. Let them sit for a while & it's a bit** to get off.

 

[lpreddick]

please, nobody talk about powder residue forming a "sine wave".

 

[hawghunter]

On our 6ppcs we called them squiggles ;D :

 

[lpreddick]

i believe powder residue on necks is a given. powder residue on the shoulder suggest low charge or a case short in the chamber...the shoulder not lightly touching end of chamber(headspace). powder residue on CASE BODY suggest very low charge or very short case. i see strange patterns(sine waves, squiggles, elvis, etc.) on 6br, 22br, 6x47l, 6brx, 22brx and don't really know what they represent. i'v seen on this site that it is a good sign...don't know, but doesn't worry me. the stuff doesn't come off very well in my case vibrator and if left requires effort to get off...4-0 steel wool with or without solvent will get it off.

 

[Lightheart]

Stubborn powder marks on case necks are easily removed before you leave the range with an amazing product named "Ballistol". Spray product on a rag and 'wipe' away stain.
My 6 BR Lapua brass comes out of the tumbler looking new and shiney.

http://www.firehawktech.com/Ballistol/index.html
http://www.firehawktech.com/index.php

I have also found it to be the very best lubricant to use on my 'lube pad'.
This stuff works on the ram of my press better than anything I have tried.

At $ 8.30 a can, plus shipping, you can well afford to give it a go.

Cheers,
Lightheart

 

[lpreddick]

a CLEAN "krazy cloth" will also work, but a dirty one will smear stuff all overr the neck

 

[Hoier]

Mine comes right off in the tumbler.

 

[Steve Blair]

please, nobody talk about powder residue forming a "sine wave".

You must not be aware of the Sine Neck Optimization Theory (SNOT). The theory is that the case neck "sine wave", when spun at the same rotational speed as the bullet at muzzle exit, will produce the same frequency as the barrel harmonic vibration. If it does not, the load is clearly not optimized. The cases are really a pain to spin that fast, but the results are worth it. When the case neck sine wave and barrel harmonics are in tune, a area of 1.5-2 meters around the muzzle becomes fully in sync with the universal constant and all bullets will go through the same hole, regardless of conditions.

 

[mikecr]

Trimming excessively can cause extra sooting, which predicts higher ES.
With a good load, normal neck clearances, & trim length within 10thou of chamber end, you get sooting of maybe 1/3 of the neck. Same conditions and trimmed only 5thou reduces sooting to nil.

 

[vern]

I shoot 6PPC.
IF everything is the way it should be... IE case length, neck thickness, etc you should end up with 2 sort of horse shoe shaped light carbon areas on the neck.
You can verify that these should correspond to the location of the lugs on your bolt.
I dont remember all the whys of this but you can read about it in several books that have been written.

 

[lpreddick]

i saw in tony boyer's book that he mentioned these neck markings and the position of the lugs. do three lug bolts leave three? i can't figure how the lugs affect powder residue on the neck??? anybody explain this? many times in larger cases i'll see a very distinct carbon ring at the base of the neck that perfectly coinsides with the lowest point of the redding neck bushing's descent, suggesting a good seal from an adequate charge and subsequent pressure. SNOT indeed!

 

[Steve Blair]

I shoot a BAT 3LL and have never seen evidence that corresponds the lugs to the neck residue. Most of the time, there are one or two waves and often just a circular line around the neck. It is almost always near the middle of the neck. The neck walls are turned to .0122.

 

[Nodak7mm]

You must not be aware of the Sine Neck Optimization Theory (SNOT). The theory is that the case neck "sine wave", when spun at the same rotational speed as the bullet at muzzle exit, will produce the same frequency as the barrel harmonic vibration. If it does not, the load is clearly not optimized. The cases are really a pain to spin that fast, but the results are worth it. When the case neck sine wave and barrel harmonics are in tune, a area of 1.5-2 meters around the muzzle becomes fully in sync with the universal constant and all bullets will go through the same hole, regardless of conditions.


Steve,

I am in 100% agreement, but I feel it is necessary to point out 2 key factors that effect the end mathematical conclusion.

The first is obvious and that is in your example, you are obviously speaking to metrically designated cartridges, thus one must ensure that they input metric parameters when applicable. An example would be the 7mm Express vs the 280 Remington, the two may be physically interchangeable, but not in the SNOT premise.

And secondly, to consider ones geographical location in relation to which hemisphere one resides in. As you may recall, this will cause the sine waves to be reversed.

Regardless, as others have responded, I find it easy to just wipe the Boogers off with a SNOT rag.

Rod

 

[seymour fish]

please, nobody talk about powder residue forming a "sine wave".

Like Tony Boyer did .

 

[Hammer47]

Tony Boyer? What the hell does he know?

 

[josh shrum]

OP, some carbon on the outside of your case necks is perfectly normal. If you are concerned about the amount of carbon you could always post a picture of a few of the cases for us to see.

 

[Scarab]

Did anyone mention that work hardened brass will leave excessive carbon on case necks due to the inability of the neck of the case to seal properly during ignition.
My brass is annealed and leaves a nice sine wave about 3/16" down the case neck. When it starts to work harden the sine wave will start traveling down the neck further.

 

[savagedasher]

Just think all the carbon that gets in the chamber neck of the barrel . It so easy to soften the neck of the brass and not have it on the neck of both the brass and the barrel .
Larry

 

[LHSmith]

FWIW- this is a 5 year old thread. At least one poster is no longer with us, unlikely he will respond should someone direct inquiries his way. But still a good topic.