Actual testing for carbon in the necks vs clean necks for low ES

[denobravo]

I did a search and found 7 pages of discussions on neck carbon. WOW
I really only want actual test data
Has anyone done this ??
Since Ive been cleaning the inside of my brass I now get single digit es in 5 shot groups
I had always annealed every loading sequence, sized, trimmed etc but never got the low number
Ive tested several primers and stay with 2 main powders R23 and H1000...which is irrelevant to the test I am looking for.
JUST CARBON testing
I would appreciate anyones personal testing. I am looking for empirical data
Thank you

 

[rwj]

Seems like you’ve done your own testing and should be very pleased with the results!

 

[Twoboxer]

It always seemed to me that "clean" was an easy condition to reproduce consistently, while equalizing "dirty' would be a difficult task.

 

[Capt. Oblivious]

For me clean always gives bigger spred unless I give the necks a bit if dry lube on the inside. Best I can come up with is load 10 “dirty” cases and 10 clean cases and shoot a 10 shot or 2x5 shot groups at your desired distance. For me the bit off carbon inside the necks works better but obviously your milage may differ and the target should show you the path

 

[Laurie]

I intend to do this comparison shortly with my longstanding FTR 308 load with 25 rounds of each shot side by side off the bench over a Labradar.

I much prefer keeping the carbon in, but brushing it hard before sizing, also lubing the inside neck and mandrel expanding. I originally intended to load 100 rounds and leave the other 25 + 25 for six or more months to see how they stood up to storage and if fouling made any difference here. (I had an example of some Lapua Scenars cold-welding to new Lapua case necks a while back after a year in the cabinet, but that's the only time I've seen this in 30 plus years of handloading.) However, I now intend to sell the rifle, so it'll likely be restricted to 'fresh ammo' only.

An old long-distance BR shooting friend who has probably done more experimentation of this type than any 10 other keen handloaders aggregated always used to clean to bright metal using Twoboxer's - post #3 - rationale until he did this test many years ago and promptly changed his views on the basis of actual experience. This is a guy for whom obtaining extreme round to round consistency is an obsession and was measuring things on his ammunition long before most handloaders had even heard of runout gauges and other such tools before they were easily available and in common use.

 

[denobravo]

Seems like you’ve done your own testing and should be very pleased with the results!

yes...I have
however a question has arisen as to empirical proof, indicating my testing is merely opinion

 

[denobravo]

I intend to do this comparison shortly with my longstanding FTR 308 load with 25 rounds of each shot side by side off the bench over a Labradar.

I much prefer keeping the carbon in, but brushing it hard before sizing, also lubing the inside neck and mandrel expanding. I originally intended to load 100 rounds and leave the other 25 + 25 for six or more months to see how they stood up to storage and if fouling made any difference here. (I had an example of some Lapua Scenars cold-welding to new Lapua case necks a while back after a year in the cabinet, but that's the only time I've seen this in 30 plus years of handloading.) However, I now intend to sell the rifle, so it'll likely be restricted to 'fresh ammo' only.

An old long-distance BR shooting friend who has probably done more experimentation of this type than any 10 other keen handloaders aggregated always used to clean to bright metal using Twoboxer's - post #3 - rationale until he did this test many years ago and promptly changed his views on the basis of actual experience. This is a guy for whom obtaining extreme round to round consistency is an obsession and was measuring things on his ammunition long before most handloaders had even heard of runout gauges and other such tools before they were easily available and in common use.

I hope you do the test.
Before you sell the rifle.
The now very common ultrasonic cleaner gives carbon free necks so the old brush method isnt needed to produce clean necks

 

[JEFFPPC]

I did a search and found 7 pages of discussions on neck carbon. WOW
I really only want actual test data
Has anyone done this ??
Since Ive been cleaning the inside of my brass I now get single digit es in 5 shot groups
I had always annealed every loading sequence, sized, trimmed etc but never got the low number
Ive tested several primers and stay with 2 main powders R23 and H1000...which is irrelevant to the test I am looking for.
JUST CARBON testing
I would appreciate anyones personal testing. I am looking for empirical data
Thank you

I have two long range bench rifles. My ES with current loads is 1 and 5. I only brush the necks 1 pass with a nylon brush.

 

[mikecr]

I'll go ahead and predict that a [clean -vs- fouled] test will show no difference whatsoever.
This, because bullets are not pushed out of necks, but released by neck expansion.

 

[dgeesaman]

I'll go ahead and predict that a [clean -vs- fouled] test will show no difference whatsoever.
This, because bullets are not pushed out of necks, but released by neck expansion.

Ah, but the bullet is under pressure too - so while the neck will be pressed to expand and reduce it's grip on the bullet, the back of the bullet is being pressed to break loose from the neck and start moving forward. When there's less dry friction the bullet will start moving sooner.

Naturally what really matters is which friction situation releases most consistently.

 

[Richard Coody]

really guys. this subject has been beaten to death.

like most things in shooting and reloading its what works for you. there is and never will be a definitive answer. you are not going to convince they guy that does it different your way is the right way.

 

[brantfredrickson]

I'll go ahead and predict that a [clean -vs- fouled] test will show no difference whatsoever.
This, because bullets are not pushed out of necks, but released by neck expansion.

I too envision neck expansion as the bullet is engraved by the rifling. But on a squib the primer will move the bullet to the rifling holding the bullet in the beginning of rifling as the shooter extracts the brass. On a squid the necks don't expand. I suspect a clean versus carbon coating has an effect on initial bullet movement to the rifling. Of course this is pure speculation!
PS: For my rifle, my bullets, my cartridge, and my load I leave the neck id's carbon coated.

 

[denobravo]

really guys. this subject has been beaten to death.

like most things in shooting and reloading its what works for you. there is and never will be a definitive answer. you are not going to convince they guy that does it different your way is the right way.

well if it has been beaten to death....
WHERE IS THE TEST AND RESULTS
and if you are sure that NO ONE will benefit from the results and change their procedure, why do we test and question each other?
You seem to have been on here a long time and as a gold cont I would think you would have at least something positive to say about ballistic research.
Maybe you cannot be taught, but I and many others are egar to learn and adapt.
"never a definitive answer" you say
WOW why are you here if testing and results dont matter??

 

[savagedasher]

My ES is around 5 on my good
cases
I don’t see any read to test or change
And they do have carbon in them
They always get cleaned with corn cobs and walnut shell before loading

 

[mikecr]

I don't have a light speed fiber-camera installed in a chamber throat, but I can provide anecdotal observation. I can coat bullets with tungsten disulphide (WS2) which has a friction coefficient lower than moly and way lower than graphite. Here, bullet seating is far lower than with uncoated bullets, but muzzle velocity does not change With this.
WS2 does not cool a charge like moly(which reduces MV).
It is very close to carbon fouling in every regard except friction.

Now I know that a bullet is pushed against that friction by burning powder or primer. That eventually charge pressure will overcome that friction and move the bullet. The lower the friction, the lower the pressure needed to push that bullet. And if that bullet is pushed prior to pressure peak, that would affect MV.
But I also know that increasing bullet friction alone, without increasing grip(tension), does not affect MV.
This confirms to me that bullets are released via neck expansion (loss of grip) prior to overcoming any pull force from friction. Something I was actually taught 43yrs ago in a reloading class.

This passes tests, perhaps all tests (which would make it a truth).
It's easy to increase bullet friction/pull force and test yourself. Take a neck and bullet to squeaky clean, loaded with the rest. Note the increase in seating force for this condition, and watch the chrono for a difference with that round. None.

 

[eric n]

I don't have a light speed fiber-camera installed in a chamber throat, but I can provide anecdotal observation. I can coat bullets with tungsten disulphide (WS2) which has a friction coefficient lower than moly and way lower than graphite. Here, bullet seating is far lower than with uncoated bullets, but muzzle velocity does not change With this.
WS2 does not cool a charge like moly(which reduces MV).
It is very close to carbon fouling in every regard except friction.

Now I know that a bullet is pushed against that friction by burning powder or primer. That eventually charge pressure will overcome that friction and move the bullet. The lower the friction, the lower the pressure needed to push that bullet. And if that bullet is pushed prior to pressure peak, that would affect MV.
But I also know that increasing bullet friction alone, without increasing grip(tension), does not affect MV.
This confirms to me that bullets are released via neck expansion (loss of grip) prior to overcoming any pull force from friction. Something I was actually taught 43yrs ago in a reloading class.

This passes tests, perhaps all tests (which would make it a truth).
It's easy to increase bullet friction/pull force and test yourself. Take a neck and bullet to squeaky clean, loaded with the rest. Note the increase in seating force for this condition, and watch the chrono for a difference with that round. None.

Do you see a poi or group size change with clean vs dirty necks?
I’ve tested squeaky clean vs mandrel, brushing, dry lubes, wisp of steel wool on a brush and nothing but I never checked it against the chrono, only target. Curious what others see...
Thanks

 

[TC260]

I much prefer keeping the carbon in, but brushing it hard before sizing, also lubing the inside neck and mandrel expanding. I originally intended to load 100 rounds and leave the other 25 + 25 for six or more months to see how they stood up to storage and if fouling made any difference here. (I had an example of some Lapua Scenars cold-welding to new Lapua case necks a while back after a year in the cabinet, but that's the only time I've seen this in 30 plus years of handloading.) However, I now intend to sell the rifle, so it'll likely be restricted to 'fresh ammo'.

Slightly off topic but I have some 30ish year old handloads (223, mil-surp brass) that the last time I fired had a bunch of split necks. Seemed like ~50% loss rate and I wondered if some type of cold welding effect could be contributing to the high failure rate.

So as an informal experiment I was going to reseat the bullets by say 0.005" and shoot 25 of each and see if there's a difference in accuracy, velocity, and failure rate. A simple exercise like that won't prove anything one way or another but it won't cost anything and I'm going to shoot the ammo up anyway so might as well try to learn something from it.

 

[Laurie]

Most likely the long-term effect of neck tension on the bullet caused those splits allied to previously reloaded brass. This was very common on old .303 British cordite loaded military ammo. Because the charge was a bundle of cords it was installed in a part-completed case, the case shoulder and neck only formed afterwards. For obvious reasons it couldn't then be re-annealed leaving the necks a bit hard. They would then crack of their own accord after 20-30 years in storage. I saw this in the contents of a sealed can of (I think) South African Mk VII where around half the case-necks had split despite their apparently being in perfect condition, nice and clean and shiny as if they'd been made the day before the can was opened.

 

[jlow]

Well it’s complicated because as much as we would like simple answers, the real world is anything but.

For example, there are many ways to clean the inside of the neck. Even if one cleans only with SS media, it does not mean all the carbon is removed in all situations. This is because the degree of clean is affected by things like how much pins you use, how many cases were cleaned in a batch, how long do you clean, the chemicals used etc – there are no standards and everyone use slightly different conditions, the ones they feel works for them.

Of course, apart from the cleaning, I doubt very much many do not reconstitute the lube and there of course are many solutions. There is zero doubt that carbon is useful for consistent neck tension, the only real question is can one clean a case with a method that cause you to lose some carbon because you want to clean the case and especially the primer pocket, that does not have a detrimental effect on neck tension?

 

[Richard Coody]

well if it has been beaten to death....
WHERE IS THE TEST AND RESULTS
and if you are sure that NO ONE will benefit from the results and change their procedure, why do we test and question each other?
You seem to have been on here a long time and as a gold cont I would think you would have at least something positive to say about ballistic research.
Maybe you cannot be taught, but I and many others are egar to learn and adapt.
"never a definitive answer" you say
WOW why are you here if testing and results dont matter??

well like i said. whatever works for you. you will have to do your own testing. i have done mine and know what works for me. i chose not to argue about it. i am quite sure if i posted my findings many would chime in about how wrong i am.

now i also do things differently with rifles with different purposes. many reloading procedures are a complete waste of effort if the rifle isn't capable of showing the difference on target.

but i well know what it takes for me to get from here with load.development.

to here after load development complete