best way to fireform brass

[bigedp51]

What is the benefit of lubeing your cases? Ive never heard of fireformed cases getting stuck in the chamber to begin with.

When water, oil or grease is on the cartridge case or in the chamber, it prevents the brass cartridge case from gripping the chamber walls. The water or lube allows the case to be pushed against the bolt face without gripping the chamber walls and prevents case stretching in the web area when the case is fired.

Below a cartridge case being fired and the case is gripping the chamber walls. The red web area in the animation below is under the greatest strain and is prone to stretching if the head gap clearance is large enough, this stretching action leads to case head separations.

The problem with oiling/lubing cartridge cases is it doubles the force or pressure on the bolt and can cause damage to the firearm.

The British at one time required all firearms to be inspected and re-proofed when the firearms changed hands. The British used oiled proof test rounds for this purpose on commercial firearms. The practice of using oiled proof rounds was stopped in Britain for re-proofing because it was found they were actually damaging these firearms with excess bolt thrust during testing.

Below a M16-A4 bolt damaged by a oiled cartridge and excess bolt thrust.

Some people think their rifles are made with Kryptonite and lubing cases and even Super Man can't hurt their rifles. Do you remember what the H.P. White Laboratories said about the repeated effects of excess pressure on firearms. Excessive bolt thrust sheared the locking lug off the rifle below.

 

[Rock Knocker]

Those are quite detailed descriptions of whats wrong with lubed cases, and its good for people to see but i fully understand the dangers of lubricated cases. But i was wondering what the benefit of a lubed case would be? why would someone even suggest to oil a case?

 

[fdshuster]

Not argueing the issue one way or another, I'm not knowledgable enough, but I do know that if I am not careful about completely drying out my chamber(s) after cleaning, and leave just a small trace of solvent in the chamber, I will get very hard bolt lift for the first 2 to 4 rounds fired. Ran this by my gunsmith the first time I experienced it, and the first thing he said was "you're not completely drying out the chamber, leaving it wet". After the next cleaning, when thinking the chamber was dry, checked it with my borescope, and sure enough, it was still wet. Now make sure it's dry by using a mop in the chamber, and sometimes a light application of brake cleaner. Have never had the problem since. Question: how is a partially wet chamber any different from a lubed case? I don't know, just asking. ???

 

[Cameron SS]

I think Big Ed has me convinced of the ills of lubing cases. I'm a military shooter, and just checked all our publications on weapons operation and maintenance. Every single one of them states emphatically to keep the bolt face and chamber bone dry of oils and moisture. Doesn't go into much detail why, but I think Ed has filled that in.

Like Rock Knocker, I am curious as to why people would continue to use such a process in the face of strong evidence against.

Is there any benefit, real or perceived to this method?

Jo 191145 Said: "The lube allows the brass less stick and the chamber pressure forces the case back against the bolt face. Basically allowing the brass to stretch along its entire length."

If thats true, and preserving case life is ideal, wouldn't the case lubing advocates want to lube their cases every time, not just during fire forming?

Asides from the expense of the components, is there any thing wrong with the conventional method of loading light, seating long and calling it a day?

 

[jo191145]

Cameron I agree.
Never lube a case in a military rifle. They are NOT designed to handle the pressure.
You'll notice all the conservative loading data for the AR's M1's etc. Theres a reason for that.
Go back further to the bolt action milsurps. Personally I would'nt want to put any undue forces on them either.
Hey, I'm not a milsurp guy. Perhaps theres some robust military actions out there somewhere. For the most part they're very weak compared to todays custom bolt action rifles. I'll even throw Savage actions in the mix. I have a lot of faith in them but thats just me. YMMV

Why would you need to lube a case thats already formed to your chamber? Once is enough would'nt you say?
A popular misconception might be the term fireforming. Usually those who lube cases are not firing 6BR brass in a 6BR chamber where a few thousandths gets the job done. They are radically altering one type of case to create a totally new one.
They're also not using full house competitive loads. Lube a case thats already formed for your chamber, throw a good charge behind it and like frank learned. Troubles coming your way.

Simply jamming a bullet in the lands is no quarentee the firing pin will not drive it in further. Either into the lands or into the case. Right back at square one. It will make it much more likely to go boom. Thats about it.

Personally i've never lubed a case. I understand why its done and somewhat how its done. Nothing like real expierience though. i'm simply trying to explain the why without going into great detail. Just not in a typing mood ;D i'm neither advocating it or not. Devils advocate perhaps.
Let the Gods of BR lube they're 220 Russians and make PPC's. Theres a reason many choose that method
I would opt for a false shoulder myself whenever possible.

My PPC came with 200pcs of formed brass. Thats enough to wear out 20 barrels. I doubt I'll be needing to lube anything soon.

 

[BoydAllen]

It should be pointed out that when Tony Boyer, or any other short range (1-200 yd.) Benchrest shooter is fire forming, it is very likely that a .220 Russian case is being made into a 6PPC, and due to the significant difference in volume of the un fire formed case and the finished product, if a powder that is normal to the 6PPc is being used, in conjunction with a bullet of the same description, that the pressure is automatically limited to well under what a typical 6PPC load would be.

The reason that I bring this up is that some who read this thread will be looking for advice as to how to "fire form" brass in a chamber that is already a pretty good fit to the brass, in a situation where "normal" or above normal pressures can be achieved due to the close match in before and after volumes. It is in these cases in particular that lubing of cases is to be avoided because of bolt thrust considerations. If you need to adjust the longitudinal fit of cases in a chamber, the false shoulder method can be used without bolt thrust issues, if the load is correct.

 

[bigedp51]

The advice of lubing cartridge cases has reached epidemic proportions in the gun forums and this advice is out of control. Imagine a so called "expert" telling people in a Lee Enfield forum to lube cartridge cases in a 100 year old rifle to cure headspace problems. The British military used oiled proof rounds to seat the bolt lugs to the receiver lug recesses and the bolt head to the bolt body on new Enfield rifles. If the headspace increased .003 after proofing with the oiled proof round the rifle failed proof testing due to excess bolt setback. These same Enfield rifles were later adapted and converted to fire the .308/7.62 NATO in excess of 50,000 CUP so please don't tell me your "modern" rifles are designed for higher pressures and made of Kryptonite.

Military rifles are made stronger than commercially made rifles and proofed to higher pressures. This doesn't mean that that a military rifle fired with a wet chamber or ammunition will not suffer abuse and abnormal wear.

I recently sold off many of my Enfield rifles in order to buy a few "modern" rifles to help cure chronologically gifted eyesight. (rifles with scopes) To my surprise the Remington rifle below had only one locking lug making firm contact with the right lug barely touching with only a single scratch mark across the lug surface.

I imagine a full pressure oiled cartridge would have seated the lugs, BUT it could also cause the single bearing lug to shear off.

Even with form fitting neck sized cartridge cases in your chamber the firing pin will drive the case forward approximately .001. This "dry" cartridge case will stretch and spring back exerting less force on the bolt face over a shorter period of time verses a lube cartridge case.

Now think about the already smooth chrome chamber on the M16-A4 and firing a lubed cartridge case or my Remington 700 with one lug touching from the factory. Now what is the percentage of people in the world with custom made rifles with both lugs making 100% contact and you might understand why I'm being a pain in the back side on this subject. The advice of lubing cartridge cases is already out of control in "ALL" the gun forums and needs to be brought back under control.

Now do a search at the front of our forum at http://www.accurateshooter.com/ on fireforming cartridge cases.............you wont find a single word about lubing cartridge cases.

 

[jo191145]

Military rifles are made stronger than commercially made rifles and proofed to higher pressures.

Wish I had known that sooner. I've got an old 30-40 Krag in the safe doin nothing and an extra 6PPC barrel floating around. Think I'll screw them babies together and go after some Hall of Fame Points. Anyone care to sell me a life insurance policy? ;D ;D
Anyone with Quickload care to calculate how much pressure a PPC is running at 3450fps with N-133? That would be an interesting number.

Sorry to hear about your Remington Ed. Shame to pay for two lugs and only get one.

I really do agree with you on the lube thing. Just not as emphatically. My WAG would be 99% of gunowners should'nt ever consider it. 99.9% of the population aren.t performing brain surgery either. That does'nt mean the Brain Surgeons are wrong.
Hows that for twisted logic ;D I'm done here. we've covered the points well enough. take Care.

 

[HolyMeekrob]

Okay, I've tried my best to keep up, but if I'm asking something that's already been answered, sorry, there was a lot to try to cover.
But since the topic has (sort of) already come up, I'd like to know how people with ARs fireform their brass.

 

[spclark]

... I'd like to know how people with ARs fireform their brass.

I think the traditional way - load 'em & shoot 'em - most common.

False shoulder (when indicated) will keep cases positioned properly, regular rifle propellants behind typical bullets, whether fired in practice or competitive events. Certainly no lubed cases.

I'd be one who'd avoid using fillers (COW) for fear of screwing up the gas tube / bolt system.

 

[HolyMeekrob]

Certainly no lubed cases.

I'd be one who'd avoid using fillers (COW) for fear of screwing up the gas tube / bolt system.

That's pretty much what I was after, thanks.

 

[bigedp51]

The United States did not use oiled proof cartridges to proof comertial or military small arms and the British did. Please read the following carefully about oiled cartridges and the "added" bolt thrust it creates for testing the receiver breech mechanisms. (19 tsi = 46,000 CUP or 49,000 psi)

The following is from the British 1929 Textbook of Small Arms.

Here in the U.S. we used the "radial" copper crusher or transducer method of measuring chamber pressure from the "side" of the "dry" cartridge. The British used the "axial" base crusher method at the very base of the cartridge case and used an oiled cartridge to get the total actual thrust on the bolt.

Below the red arrow indicates where the British base crusher was located to get a true reading of chamber pressure and bolt thrust.

(Under the British base crusher standards described below, proof loads ran 30 to 45% above normal. To maximize breech thrust, proof cartridges were oiled before firing.)

In Britain, a third set of crusher standards were developed, using a "base" crusher. The crusher was a short, thick tube placed behind a piston at the base of the cartridge, and the firing pin passed through the center. The cartridge case was well oiled before firing, to minimize cling to the chamber walls (if not oiled, the indicated pressures were about 25% lower). To prevent case rupture on set back of the base, the crusher was first deformed in a press to a pressure a bit lower than that expected in firing. The units were generally stated in British long tons per square inch, or tsi. Pressures indicated by this method run 10 to 20% below those indicated by radial crushers. Kynamco in England still rates their production cartridges with this method.


Cartridge Pressure Standards
http://kwk.us/pressures.html

To this day the British Military still uses oiled proof test rounds to simulate the stress put on small arms under combat conditions. And your custom made bench rest rifles were "never" tested this way.

 

[jo191145]

Your point is????????? GOT IT!!!! God I'm so dense!!
Don't use the Krag action use a Lee Enfield!!!!!
Obviously the most advanced strongest action ever tested/designed by man!!!
Someone should tell those Brits to stop lubing cases tho. Inheritantly dangerous.
You applaud the Brits for lubing cases rated +30-45% standard operating pressures in hastily built loose tolerance antique rifle actions. Yet you vehemntly oppose any American who lubes cases at -30% standard operating pressures in precision crafted modern firearms. Union Jack tattoo's Ed????
Wheres my bang head against wall smiley ;D

http://www.international-benchrest.com/

Within you'll find detailed equipment lists. Peruse at your liesure.
When you find someone using a Lee Enfield give me a holler.
Heck you find anyone using any WWII surplus scrap actions let me know. That would be the biggest news since WWII broke out.
Its been fun Ed. Good to know some things never, absolutely refuse too, change. Take Care............

 

[bigedp51]

Your point is????????? GOT IT!!!! God I'm so dense!!
Don't use the Krag action use a Lee Enfield!!!!!
Obviously the most advanced strongest action ever tested/designed by man!!!
Someone should tell those Brits to stop lubing cases tho. Inheritantly dangerous.
You applaud the Brits for lubing cases rated +30-45% standard operating pressures in hastily built loose tolerance antique rifle actions. Yet you vehemntly oppose any American who lubes cases at -30% standard operating pressures in precision crafted modern firearms. Union Jack tattoo's Ed????
Wheres my bang head against wall smiley ;D

http://www.international-benchrest.com/

Within you'll find detailed equipment lists. Peruse at your liesure.
When you find someone using a Lee Enfield give me a holler.
Heck you find anyone using any WWII surplus scrap actions let me know. That would be the biggest news since WWII broke out.
Its been fun Ed. Good to know some things never, absolutely refuse too, change. Take Care............

The United States military, the British military, the fire arms industry, the reloading industry and the amunition manufactures tell you to "NOT" lube your cartridge cases.

And you case greasers without any pressure data or test equipment want to tell the world to ignore all the warnings because you "experts" know better.

What is so hard to understand, a oiled or lubed cartridge case delivers "TWICE" the force, pressure or both thrust to the bolt and locking lugs.

The firearms industry is having problems with the new short magnum cases and bolt thrust. And a P.O. Ackley improved cartridge case delivers even "LESS" bolt thrust and you people still want to argue the point.

"Ackley Bolt Thrust Tests.

I have long wondered about P.O. Ackley’s claims about bolt thrust. I have started some tests to see if more modern tools can tell us more about bolt thrust than Ackley was able to learn from his test. On page 139 of volume 1 of Ackley’s “Handbook for Shooters and Reloaders” he discusses pressure, and I quote, “The usual method of measuring pressure is by means of crusher cylinders, so as to measure the pressure at right angles to the axis of the bore about midway along the body of the chamber. This method gives a fair idea of the actual chamber pressure exerted upon the walls of the chamber in all directions, but bears little relationship to the amount of this pressure actually transmitted to the bolt or breech block in the form of thrust.”

Ackley believe that minimum body taper reduced bolt thrust. So, I set out to see if it does or not. First I set up a 30 caliber barrel in a test fire jig. I started with a 30-30 WCF chamber, firing factory ammo. Utilizing the Pressure Trace system I installed a transducer on the barrel to collect pressure data.

We also mounted a transducer over the recessed breech in our barrel to see if we might measure longitudinal stretch. This did produce measurement, but only time will tell if they have any value. At this point in the test I suspect that the data we are getting is too flawed to decisively answer any questions.

Its important to lay out some facts at this point.

1. SAAMI maximum pressure in the 30-30 Winchester is 42,000 PSI.

2. Federal Factory ammo was used for the first phase of the test.

3.Our firing mechanism is adjustable for headspace and the firing pin is adjustable for length so that we can fire with excessive headspace.

We learned something right away; while firing the factory ammo in the 30-30 Winchester chamber and collecting pressure/velocity data, I decided to test various degrees of excessive headspace and see the results. Interestingly, I set the breech with .010″ (10/1000 of an inch) headspace. The fired cases did not move back at all, the primers did back out the exact .010″ distance. Ackley did not test this in his series, so right away we learned that the 30-30, which is considered to be a low pressure cartridge will adhere to a dry chamber under pressure, and the brass can contain the factory level pressure without stretching.

All brass was carefully messured, no head expansion or stretching in length occured. Next we rechambered the barrel to 30-30 Ackely Improved. The same factory ammo was used to fire-form cases. The same test was perform with headspace, even during fire-forming the cases did not move back or stretch in length.

We are now at the stage of the test where we are working up loads to see how much velocity we get at the same pressures as our factory ammo. This is always a hotly debated subject, so it will be interesting to have concrete information to share.

Check back soon to see how things progress with this test. BTW, I am giving you the short version here, the full test and all ballistics will be included in my book on P.O. Ackley when it is published."

Below a "DRY" cartridge being fired and the chamber walls have "MORE" pressure "pushing" on them than the bolt and bolt lugs. When oil or grease is added to the cartridge you have twice the force or thrust on the bolt face and bolt lugs and bolt in the picture below would turn red in color in the same test.

A Remington model Seven .243 bolt action rifle above and below is "not" British and the pressure "facts" are below.

VERY LOW FRICTION.... Very low Coefficients of Friction of 0.01 to 0.11 are very difficult to obtain without extremely polished surfaces and grease. Note that when there is extremely low friction not only does the bolt face load increase but the plastic strain in the case head also increases. There needs to be some axial tension in the wall of brass case wall to increase the resistance to yielding and formation of plastic strain.

From Varmint Al's web page.
http://www.varmintal.com/a243z.htm

With all due respect : everyone is entitled to "my" opinion. ;D

Along with the "FACTS" I have posted from the firearms industry on greasing or oiling cartridge cases.

 

[jo191145]

You wrote.
Note that when there is extremely low friction not only does the bolt face load increase but the plastic strain in the case head also increases.


Varmint AL says.
CONCLUSION.... A polished or low friction chamber decreases the plastic strain near the case head and reduces the chance of case head separation on subsequent reloads.

Just want to make sure you got that right before the 1st printing. Opinions are nice but its right there in the numbers you printed and the info from Al you omitted.

No ones denying bolt thrust here. Lets keep it factual OK.

 

[bigedp51]

You wrote.
Note that when there is extremely low friction not only does the bolt face load increase but the plastic strain in the case head also increases.


Varmint AL says.
CONCLUSION.... A polished or low friction chamber decreases the plastic strain near the case head and reduces the chance of case head separation on subsequent reloads.

Just want to make sure you got that right before the 1st printing. Opinions are nice but its right there in the numbers you printed and the info from Al you omitted.

No ones denying bolt thrust here. Lets keep it factual OK.

Dear jo191145

Again you are wrong, everything in blue is from the websites I quoted and linked.

Varmint AL wrote (quote)

"Note that when there is extremely low friction not only does the bolt face load increase but the plastic strain in the case head also increases."

I linked the page so "YOU" and anyone else could read the facts and "ALL" the information.

Varmint AL doesn't recommend lubricating cartridge cases, what he is recommending is polishing rough chambers to reduce case stretching. The chromed chambers in our M16-A4s are as smooth as needed and our U.S. Military still tells you to "NOT LUBE YOUR AMMO".

NOTE: The chamber on my No.1 Enfield in 7.62 NATO had a smooth chrome chamber and I would never think of lubing any ammo in any rifle.

So please jo191145 in the future don't misquote me to get the last posting in the thread.

 

[Forum Boss]

I'm going to lock this one up, we've all been back and forth on this and other threads.

But please note:

1. Our official recommendation, consistent with the stated safety policies of powder-makers, brass-makers, and rifle-makers, is DO NOT LUBRICATE your cases. This is for all the many reasons stated.

2. That said, some benchrest shooters such as Al Nyhus have had success with light lubrication used in fire-forming situations where the case can expand its internal dimensions on firing. We still do not recommend lubing cases, but this is an instance where some shooters, using custom actions, have been able to pull it off. We recommend that you attempt your fire-forming process with clean dry cases first. When forming Dasher and BRX brass with a false shoulder method, we found that lubing was completely unnecessary.

If something is potentially dangerous, if it is counter-recommended by brass-makers, and it is not necessary, why do it?