New to AR-15's

[TacticaLogic]

Note to C. Richard Archie: Please read my sentence below (marked with a **) regarding the markings on the referenced fired case and provide your insight, would you? I consider you to be more knowledgable regarding reloading and reading once fired cases...

Wow... I guess that if you own the domain name "Box O' Truth" it means everything on your website is the truth... By that standard, I am going to purchase the domain name "RichestManintheWorld.com" and see if that works for me...

There are several problems with this information from "Box O' Truth"... First, I can tell you, as can anyone else that has fired an H&K 91 or Cetme (with the fluted chambers) on a regular basis and then examined their fired brass: that the black residue that you are seeing on the case of the South African ammunition is not normal carbon build-up but is indeed lacquer build up. Ordinary blow-by carbon such as is being suggested by the thread at does not have well-defined edges as is being shown in the pictures. Blow-by carbon build up is more grey-black and has more "feathered" edges. Then, the article is stating that the South African is actually too brittle and that is causing the problem. The poster tries to make a case for this by saying that with soft brass the extractor will pull through the case rim, while with brittle brass the case rim will be broken off - this is complete and total B.S. I don't care if the brass is considered soft or brittle - with 50,000 p.s.i. knocking the bolt carrier back the cartridge case head will be ripped off or ripped through regardless of soft or brittle if the case is indeed stuck in the chamber. The difference in whether or not you want to call the case head damage "ripped' or "pulled through" could be the difference in how worn the extractor is for that matter. **If the brass of the case is too brittle to properly expand, why is it so obvious to those of us familiar with reloading to see that the case expanded to fit the chamber just forward of the base of the fired case (which is what normally occurs, and is the reason that benchrest shooters only "neck size" their cases in order to maintain that tight chamber fit)? That dark ring you see around the case is where it expanded and picked up the lacquer residue... If the chamber was not coated with lacquer residue, this ring around the case just above the base would be slightly shinier than the rest of the case and would have slight, small, almost invisible striations where it was pulled from the chamber instead of a black ring**.

If you reload, I can tell you another way to prove that what they claim to be carbon build up is not carbon build up but is indeed lacquer residue: Take some fired brass that has been fired through an AR-15 after some 80 or so rounds of lacquer-coated Wolf has been run through it. Assuming that you do not have a case head separation and that you now have intact brass with markings that resemble those shown in the pictures, you are ready. Place that fired brass in your tumbler and use the media of your choice (treated corn-cob or treated walnut hulls) and tumble it for 12 hours or so. If the case really had carbon build-up there may still be some discoloration and there may be some spots not quite as shiny as the rest of the case because the media had to work its way through the carbon build up, but it will indeed remove the carbon. With brass that has lacquer build-up from being fired after Wolf ammo, when you pull it out of the tumbler, you will see shiny brass everywhere there was no black, but you will also still see the black spots on the brass just as it was before, but now it may have a slightly more green tint to it since it has been in the tumbling media. I have to use a different cleaner (such as 'throttle body cleaner' from the auto parts store) to get the lacquer off of the case. I run into this when I pick up a drum load of 5.56NATO/.223 brass from one of the ranges I use. (Throttle body cleaner or carb cleaner works well for cleaning the residue from the cases and is very metal friendly - won't damage steel, brass or aluminum. One quick spray disolves the residue and you can quickly wipe it away.)

Even "Box O' Truth"'s own test is flawed in that they experienced problems after firing 80-100 rounds of Wolf and then switching to the South African ammo, but then when they went to test the Israeli ball and the M-193 ball they had fired only 25 rounds of Wolf. Gee that is some real scientific work, there. But it's got to be the truth right? Since the name of the website is "Box O' Truth?" Give me a break...

Above, wlhawk advised that the operator's manual from DPMS warns against lacquer coated steel case ammunition. It goes beyond that... DPMS, as well as several other manufacturers will consider your warranty void if they find evidence of lacquer-coated steel ammunition having been fired through the weapon. Try sending back an AR-15 that is beating the firing pin retaining pin into a "u" shape so that you can not remove it without a lot of force and a pair of pliers... The first thing they are going to do is look at the chamber for lacquer residue. When they find it, they are going to ask you if you want them to procede with the repair work since you are now going to have to pay for it, as your warranty is no longer valid. THAT RIGHT THERE SHOULD SPEAK VOLUMES. Some will say, "so what, it works" and "it's cheap, so I get to shoot more." But when you have a catastrophic malfunction that blows part of the receiver into your face, that savings doesn't mean a whole lot.

I'm not just some hack on here just spouting my opinion for the sake of argument... I teach this stuff for a living. My company has been the company of choice to teach the AR-15/M-16 Armorer's course for the International Law Enforcement Educators and Trainers Association (ILEETA) Annual Training Conference (training the trainers) for several years running. We have also been the company of choice for the same course (again, training the traners) for the International Association of Law Enforcement Firearms Instructors (IALEFI) Annual Training Conference for several years. And while our friend Ron Carter does the main factory training work for Sabre Defence, our armorer's course is accepted by Sabre Defence as proper instruction for those agencies that have purchased AR-15/M-16 weapons systems.

A story that has more and more truth to it as I get older, even though I haven't heard it in years: When I was in my teens, I was always messing with my car, trying to make it do something the factory had not meant for it to do... Turn a needle valve here, advance timing there... My dad once asked me "Son, those engineers that designed that car had years of education,understood what they were trying to accomplish, and got paid very good money to do so. Do you really think that you can take the same exact parts and get more out of it?" And he was right - I never got more out of the car performance-wise, even if I did try to talk myself into thinking I was. The lesson: Sometimes it is best to stick with what the engineers designed and specified, otherwise you may end up spending more than you would have if you had just followed their instructions. The AR-15/M-16 weapons system is a very precisely machined piece of equipment, meant to be fed brass cased ammo... Feeding it lacquer-coated Wolf goes against what the engineers are advising.

But hey... If you want to shoot Wolf... go right ahead. Don't worry about a warranty. Just keep on shooting... But please don't post on the forum some sob story about how you are suffering ripped case heads or worse when it happens...

I'm done with this topic... Like the old saying goes, "You can lead a horse to water..."

Mike

[C. Richard Archie]

The pressures (and heat) generated during firing a round would expand any case, soft or brittle. 40-50,000 psi is going to force the brass/steel against the sides of the chamber. If the case is too brittle, (or the chamber too large), the case ruptures, every time. One must keep in mind, ammunition, to chamber, must by necessity, be smaller than the chamber itself, or you can not get the round in.

There is enough heat and pressure generated to do a lot of things to the case. For those who uniform their primer pockets, it is apparent that the primer will sit below the case head. Inspection of that brass after firing will show it to be flush, this because the case head expands and the primer backs out and is stopped from hitting the shooter in the eye by the bolt face. The case expands to fill the "void" of the chamber and is driven back over the primer, resulting in the primer being flush.

The main body of a case expands to fit the camber upon firing, and "sticks" there. Brass, with it's lower melting point than steel, will flow to fit the chamber, Hot loads will show flow into cuts in the extractor cuts, one of the signs of over pressure. This phenomenon explains why once can "fireform" brass, most notable in wildcat applications, but it happens in every instance, whether it is apparent or not.

Chambers do not support the case head normally, allowing them to expand far more than the body of the brass, (hence the ability of the much thicker portion of the case head to expand and allow the primer to "back out"). The brass “flows” under heat and pressure, most notably by lengthening the case, requiring trimming from time to time to allow overall case length to stay within parameters. The brass also flows backwards, and as the chamber wall is the “mold” the case appears to be uniform, but the danger is thinning on the inside of the case, leading to insipient case separation, as the case elongates with flow forward and backward.

All this takes place in parts of a second. Brass being a more malleable substance is a far better material for cases, as it fills the voids in a chamber better than steel. Also, it’s rate of oxidation, “rust” is slower and much less evident. Steel on the other hand will rust quickly and the scale produced will keep the round from chambering, requiring a coating of some type to preclude that. Wolfe has used the lacquer to date. The same temperatures that “melt” the casing will do the same to the coating, and as the case, and coating, cool rapidly as well the lacquer deposits on the spent case, and chamber wall. Any dust, dirt or carbon that is present will get compounded in the molten lacquer and wind up as a deposit. Now you have “glue” on the chamber wall with grit.

More on this later, but the short answer is, Steel cases are not the optimum.

[TacticaLogic]

@ C. Richard Archie:

Thank you, sir... Your explanation of what goes on in the milliseconds of primer strike and powder combustion is much more clear than anything I could have said.

Mike

[Underground]

If you don't have one already I would suggest considering the Robinson Arms XCR.

It is a good design which is caliber convertible, has a one piece upper with full rails, folding stock (or fixed), long stroke piston, adjustable gas, ambi safety and slide release, and a very fine trigger to name a few features. And they eat Wolf and other steel cased ammo with no trouble.

I have all 3 kits, 5.56, 7.62x39 and 6.8 SPC. I like mine enough I couldn't ever see myself buying another AR over that.