Steel Cased ammo?

rum_runner · #1 07-29-2017, 06:56 PM

As a NEW owner of a M&P AR platform...Sport 2, I have seen, on the net, and have been advised by a Friend, who has built 8+ AR's off of Palmetto parts, NOT to put steel cased rds thru my M&P.
Why?
My CETME, PTR, and AK's "eat" anything I run thru them. Brass, steel, aluminum etc,
What makes the M&P different???

hdwhit · #2 07-29-2017, 07:04 PM

Quote:

rum runner wrote:
...been advised by a Friend, who has built 8+ AR's off of Palmetto parts,...

I am not a prophet, so I cannot tell you what dreams, fantasies or rationales your "Friend" may have for this advice. Why don't you ask him and post his explanation here so that others can add their evaluation of it?

DWalt · #3 07-29-2017, 07:11 PM

Some claim that steel-cased ammo will cause undue wear of the extractor, requiring early replacement. I have seen no proof of that. An Urban Myth? I don't know.

fdw · #4 07-29-2017, 07:12 PM

I've got no problem with steel cased, nor have I had a problem with it.

andy52 · #5 07-29-2017, 07:14 PM

All sarcasm aside there is no evidence that modern made steel ammo will harm your AR in any way, and I've build a lot more then 8 AR.

PeglegJones · #6 07-29-2017, 09:44 PM

I have heard the same urban legend.

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WVSig · #7 07-29-2017, 09:51 PM

Quote:

Originally Posted by andy52

All sarcasm aside there is no evidence that modern made steel ammo will harm your AR in any way, and I've build a lot more then 8 AR.

This is not exactly true. There are reason why people recommend not shooting steel cased ammo. Some of it comes from the days when they used a ****** lacquer on brands like Wolf that when you heated up the barrel and the chamber the round would sometimes stick. Current production steel ammo does not have this issue.

The other issue is excessive wear on the barrel both bore and throat. Most people will site the lucky gunner article. Brass vs. Steel Cased Ammo – An Epic Torture Test

http://www.luckygunner.com/labs/bras...el-cased-ammo/

In this test they found:

Quote:

As indicated by accuracy testing, the steel cased/bimetal jacketed ammunition caused accelerated wear to the inside of their respective bores. While the barrel of the Federal carbine had plenty of life left, even after 10,000 rounds at extremely high rates of fire, the Wolf and Brown Bear barrels were subjected to the same rates of fire and were completely “shot out” by 6,000 rounds.

At the end of the test, the chrome lining of the Wolf and Brown Bear barrels was almost gone from the throat forward, and the barrels had effectively become smoothbores, with the rifling near the muzzles acting only as a mild suggestion on the projectiles. A throat erosion gauge could be dropped into the bore from the muzzle end with absolutely no resistance.

Most people reading this article assume that the steel case is the cause for this excessive wear but I have also seen some evidence that the excessive wear could be caused by the ****** powder used in cheap steel cased ammo. Others then talk about the bi-metal jacket being even worse. However it might just be the propellant not the case or the bullet that is the culprit.

Scroll down a bit on this thread and you will see what I am talking about.

The classic argument: Is Steel Case Okay To Shoot? - AR15.COM

Quote:

Everybody has seen this THAT article from Lucky Gunner Labs, and while it is a good article and full of good information, many people out in internet-land tend to draw conclusions that are not correct. One of the most quoted incorrect conclusions is "...steel cased ammo wears out barrels" or "…bi-metal jacketed bullets wear out barrel twice as fast as copper jacketed bullets…"

It is unquestionable that Wolf, Brown Bear and (probably) Tula steel jacketed, bi-metal jacketed ammunition will wear out a barrel faster than Federal XM193 ammunition, but the but the extra jump to "all bi-metal" vs "all copper jacketed" is not supportable. Even worse is the "steel cased ammo, wears out barrels", The type of material the case is made from has nothing to do with barrel life.

Here's why:

From the earliest day of smokeless propellant, the problem of bore erosion and wear has been a constant head-ache to owners of large number of high use guns and very expensive guns, namely the military. So, not surprisingly, they did a lot, and I mean A LOT, of research into what causes bore erosion, and how to reduce it.

There are basically two causes of bore wear - 1) heat, the flame temperature of burning propellant is anywhere from 2500 to 3000 degrees K, depending on the actual propellant (for reference, the melting point of the steel used in the barrel is 1700 degrees K), and 2) mechanical rubbing between the bullet and the barrel. Of the two, the effects of heat are probably the most damaging.

Here are some results of some US Army erosion tests done with 7.62mm Ball, M80:

Test firing.............Propellant..................... .....Jacket......No. of Rounds to.......Cause for
No...............................Type............. .....................Material....Disqualification. .......Disqualification

1..................................IMR 8138M Lot 2.................GM..............14,500.......... ...........V (1)
2.................................IMR 8138M Lot 2.................GMCS..........8,450............. ........K (2)
3................................IMR 8138M Lot 2.................GMCS........10,150.............. ........K
4................................IMR 8138M Lot 48..............GM................8,000........... ...........V
5................................IMR 8138M Lot 48...............GM................7,500.......... ............V
6................................IMR 8138M Lot 48...............GMCS..........7,850.............. ........K
7................................IMR 8138M Lot 48...............GMCS.........11,800.............. ........K
8................................WC 846 Lot AL44133..........GM..............17,300........... ...........V
9................................WC 846 Lot AL44133..........GMCS.........18,325.............. ........K

1) Velocity loss of more than 200 fps

2) Keyholing, defined as 20% or more bullets exceeding 15% yaw at 1000 inches (appox 25 meters)

The significant conclusions drawn from these results in the report this table was attached to were as follows:

1. Bullet jacket material (GM versus GMCS) does not appear to have a significant effect on barrel life. However, the GM jacketed lots all went out on velocity loss while the GMCS lots all went out on keyholing indicating that the mechanism of barrel failure was probably different.

2. WC 846 propellant is less erosive than IMR 8138M propellant.

One may note that test firings #2 and #6 differ greatly from #3 and #7, which is very puzzling as the components used were the same, and the propellant lots were the same. Also, the question of why did 8138M Lot #2 perform notably better that 8138 Lot #48, came up. In the report, the difference was written off to variations in the test barrels.

Partially in an attempt to explain the above, and also to test the usefulness of wear reducing additives, a second test was run, with stricter controls on barrel selection and more careful monitoring of various barrel parameters.

In this test several T65E1 machine guns (M1919A4s converted to 7.62mm) with chrome plated barrels were utilized. A 25 round belt was shot every 12 seconds until 500 rounds were expended. Then the barrel was allowed a 4 minute cool down period before the next 500 rounds were fired, again in 25 round increments. Bullet velocities and bullet yaw were continuously measured. Every 5000 rounds, the barrel was cooled to ambient, cleaned, measured, and samples of residue and bore fouling taken for analysis. The measuring consisted of measuring the diameter of the lands and grooves at 1 inch intervals were measured. Then the process was repeated until another 5000 rounds was shot, or the barrel failed due to keyholing or velocity loss.

The findings from the tests described in this report are summarized in the table below.

Summary of Results
.................................................. .................................................. ..................Adiabatic
.................................................. .................................................. ..................Isochoric
.................................................. .................................................. ..................AverageFlame.......No. of
Cartridge...........Bullet........................ ..........................CaC03...Mo03..........Te mp..............Rounds to
Lot No.................Design..................Propell ant..............(%)........(%)..............(K).. .................Disqual.

LC-SP-1368.......GMCS (1)..........Ball WC 846...........0.15............0.............2884.. ................10,417
LC 12923............GM (2)..............Ball WC 846............0.58...........0............2790... ...............18,042
FA-42-73...........GMCS.................Ball WC 846...........0.47...........0............2831.... ..............13,342
FA-2115..............GMCS.................Double Base............0..............1.05.........2889.. .................8,625
.................................................. ............Extruded
.................................................. ............Propellant
FA-2016..............GMCS.................Double Base............0................0.............291 2...................6,333
.................................................. ............Extruded
.................................................. ............Propellant

_______________________
1) Gilding Metal Clad Steel jacket (aka, bi-metal), the total jacket thickness is .021" with an outer gliding metal cladding averaging .003" thick. The core is a lead-antimony alloy with 2% antimony, softer that the GM bullet design. (Note: this is about the same cladding thickness as used by Wolf, Brown Bear and Tula.)

2) Gilding Metal Jacket, the total thickness of the jacket is .026". The core is a lead-antimony alloy with 10% antimony.

Note: All GM jackets bullets came from the same production lot, as did all GMCS jacket bullets.

Calcium carbonate (CaCO3) is an additive used to neutralize acid during the production of ball propellant. It has also been shown to reduce barrel wear, unfortunately, it also leads to increased fouling. WC846 made after 1969 was made with reduced CaCO3 content (less than .25%) in order to be used in the M16 without fouling the gas tube. At some point, WC864 with extremely low CaCO3 content was split-off as WC844, and WC846 with increased CaCO3 content was introduced as WC864+CaCO3 for use in 7.62mm, Ball, M80 specifically to increase barrel life.

You will note from the above table, and the before it, that there is a better correlation between flame temperatures and wear than jacket material and wear, especially if you know that 8138M has a flame temperature of 2770 to 2820 degrees K. GMCS jacketed bullet are only slightly harder on the barrel than GM jacketed bullets, but the choice of propellant can easily make up for the difference.

In the second test, measuring of the bore diameters did reveal something interesting. When a bore wears, enlarging of the throat tends to lead to velocity loss, as gas escapes around the bullet rather than pushing it down the barrel. Conversely, wear at the muzzle tends to lead to keyholing as the rifling loses its grip on the projectile before maximum velocity and maximum RPM are reached, therefore the bullet leaves the barrel with less spin than required to stabilize it

The measuring of the tested barrels showed the GMCS Jacketed bullets seem to open up the muzzle more than GM jacketed bullets, which would explain why GMCS jacketed bullets tended to keyhole. Not only did the land diameter increase, the groove diameter showed a similar enlargement. Possibly indicating a gas erosion phenomenon as the bullet nears the muzzle?

In all cases, the addition of calcium carbonate in the propellant drastically reduced the progression of throat erosion. Molybdeum trioxide did reduce throat erosion, but the fouling residue was so bad it made continued firing of the gun difficult (It formed in the recoil booster and prevented the barrel from sliding freely).

These are just two Army published reports that show that flame temperature of the propellant has a very large impact on barrel life. In fact, as a result of their years of study, the US Navy has adopted the simple solution to barrel erosion is simply reducing the flame temperature of the propellant and live with the reduced performance. This is the thinking that brought forth NACO (NAvy COol) propellant, and reduced muzzle velocity, and subsequently range.

(It is interesting to note that ball propellant, even though it is a double base propellant, burns cooler than 8138M, which is a single base propellant.)

The result shown in the Lucky Gunner test, are almost the exact same results as the results shown in the above two Army tests, namely, the relatively cool ball propellant used in M193 (WC 844, the same stuff as WC846 but with less CaCO3) will wear out a barrel in 13,000 to 15,000 rounds, and the reason for rejection will be velocity loss (if you look at the velocity chart for the copper jacketed bullets, the velocity loss will be more than 200 fps in about that time). We can only assume what powder Wolf, et al. are using, but it would seem from the results to be a relatively hot extruded propellant (double or single based) which has shown to wear out a barrel in about half the time as WC846/WC844, and the reason for rejection of the barrels is keyholing.

Basically, if you load up 15,000 rounds of 5.56 using IMR 8208 XBR (very similar to the stuff used in lot FA-2016), and shoot it from one AR, your not going to get through all of it before your barrel wears out even with copper jacketed bullets and brass cases.

Load up 15,000 rounds with WC844, in steel cases and copper jacketed bullets, and one barrel will survive it.

That said if you are paying $.25-$.30 for brass cased ammo like Wolf Gold, IMI, AE, Federal etc... and you shoot enough you can save money shooting steel cased ammo.

You can save $.05 to $.11 a round depending on what you are buying. If you use the Lucky Gunner article as a base line your Sport II barrel will be shot out after 6,000 rounds. If you shot exclusively steel case ammo you will have saved $300 to $600 vs brass cased ammo.

A new AR15 barrel can cost you between $100 and $400.

Aero for $179 16" 5.56 M4 CMV Barrel, Carbine Length | Aero Precision

PSA $99 PSA AR15 16" M4 5.56 NATO 1:7 Nitride Barrel - 7782495

BCM $239 BCM 16" M4 Barrel, Stripped

So even taking the lowest number if you shot the 6,000 round and you barrel is toast you can get a replacement barrel for say $150 and you are still ahead by $150. This is assuming you can install it or you have to factor in that the cost as well. Real world saving is more likely to be in the $450 range IMHO because brass cased ammo at $.25 a round is here today but only via rebate and sale pricing of AE and other Federal ammo. Over the last 2 years or so steel cased ammo has been available for $.19-$.23 a round and brass cased has run $.28-$.30 online delivered to your house.

That said I have never had steel cased ammo shoot as well in my rifles as brass. I have never shot 1" groups at 100 yards will Wolf, Tula, Brown Bear or Barnul. A lot will depend on the type of shooting you are doing but. Are you a minute of man shooter inside 100 yards or are you a bench guy shooting 200-300 trying for tiny little groups. Steel ammo IMHO will not get the job done for some types of shooting.

So if shooting 4"-6" at 100 yards is all you need and you are looking to send the most rounds down range at the lowest cost steel cased ammo is a viable option. If your needs are different then maybe stick with higher quality brass cased ammo.

Mike, SC Hunter · #8 07-29-2017, 10:22 PM

And on unrelated ammo......Most shotgun shells now have steel heads instead of brass.....cuz steel is cheaper than brass.......

agksimon · #9 07-29-2017, 11:09 PM

Bi-metal bullets are a thin copper plating, over a steel jacket, which covers the lead core. Steel, being harder than a thicker copper jacketed bullet, would have to wear out the barrel faster. If bi-metal bullets completely shoot the rifling out of a barrel at 6000 rounds, at what point does acceptable accuracy end, (which is relative to the shooter)? I would imagine long before the rifling is completely shot out. I have used Hornady steel case ammunition with complete confidence, as it uses their powder and a copper jacketed bullet, but I will not run bi-metal bullets through anything I own.

WVSig · #10 07-29-2017, 11:23 PM

Quote:

Originally Posted by agksimon

Bi-metal bullets are a thin copper plating, over a steel jacket, which covers the lead core. Steel, being harder than a thicker copper jacketed bullet, would have to wear out the barrel faster. If bi-metal bullets completely shoot the rifling out of a barrel at 6000 rounds, at what point does acceptable accuracy end, (which is relative to the shooter)? I would imagine long before the rifling is completely shot out. I have used Hornady steel case ammunition with complete confidence, as it uses their powder and a copper jacketed bullet, but I will not run bi-metal bullets through anything I own.

Right which I believe backs up the Lucky gunner + USGI data from AR15.com. It is not the case or even the bullet which is really the source of excessive wear but it is the powder.

The steel used in bi-metal projectiles are made from very soft mild steel. Bores/barrels are at least as hard as tool steel and when chrome plated are even harder. Bi-metal ammo is not going to harm a barrel if loaded with decent powder.

Hornady is using proper powders which are not creating flame temps that are too high. The steel case does not make a difference in this example. The same cannot be said for people like Wolf, Tula, Brown Bear etc... They are using much cheaper powder which I believe has a higher flame point which causes the excessive wear. IMHO YMMV

jagular · #11 07-30-2017, 01:47 AM

It's runs in my sport fine. I've had one stuck case in the 1,000+ rounds I've put through it. It may wear out your rifle more quickly, however, by the time you get to 6-8,000 rounds you'd save enough to buy a whole new rifle.

Steel cased ammo is not particularly know for its accuracy but I've found it shoots 3-4 moa which is good enough for me. Especially when I'm at the range to have fun and not worry too much about accuracy. It's shoots fine for minute of man.

rum_runner · #12 07-30-2017, 05:09 AM

Wow! I appreciate the replies. No doubt I am at the right Forum as far as what I need to know on the care and feeding of this rifle. I just want to make sure I don't break it. The M&P almost looks like a toy compared to my other rifles. I feel more comfortable with it now that I am able to get the info from much more experienced owners than myself. I really enjoy shooting it, so much so that my other rifles are beginning to look at me kind of sad (do guns have "souls"?) when I reach into the safe ...and select the 15 to take for an outing...
Fact is, I never thought I would be able to afford a good AR platform. Looks like S&W thought about us "little guys"...
Thanks again, all!

hdrolling · #13 07-30-2017, 08:20 AM

I have run steel cased through mine, depends on what the sales are at the time I'm placing an order. If I can find brass cased just as cheap then I'll buy that, but have had no issues firing steel case.

My sport II is an inexpensive AR with a "so-so" barrel, if the steel cases wear it out than I'll replace the barrel with one that's a little better.

I'm guessing your friend told you not to because someone told him not to and someone told that person not to, use to be the case back in the day and some people just haven't caught up with the times.

If you are planning on running steel case I would start off with a small amount like 20-50 rds instead of a 1000 rds just to be sure your rifles fires that ammo okay first.

robvious · #14 07-30-2017, 02:17 PM

I once avoided steel cased ammo at all costs... then I went to a machine gun shoot with a friend with the real fun toys... their weapons cost WAY more then my little semi-autos... some of historic origins... WWI and WWI vintage pieces... and if Steel Case was available in the specific caliber it was being used... that pretty much cured me of my avoidance of the steel cased ammo... I purchase what ever is needed for what I am doing... generally brass for accuracy, steel for fun...

Disabled1 · #15 07-31-2017, 01:38 AM

Quote:

Originally Posted by rum_runner

As a NEW owner of a M&P AR platform...Sport 2, I have seen, on the net, and have been advised by a Friend, who has built 8+ AR's off of Palmetto parts, NOT to put steel cased rds thru my M&P.
Why?
My CETME, PTR, and AK's "eat" anything I run thru them. Brass, steel, aluminum etc,
What makes the M&P different???

Why you should;
It's cheaper in price than brass ammo. 'Nuff said!

Can you ask said FRIEND to please come here and explain WHY NOT to use SCA? And, to please post ALL 8+ of his PSA AR's. We love AR pics around here.

rwsmith · #16 07-31-2017, 05:35 AM

I'm leery about putting steel anything in my guns. As far as steel cased ammo, though, I've never heard of any real problem. I'd presume that a malleable grade of steel wouldn't be likely to hurt hardened steel.

I reload, so I don't use steel anything, but if I had something like an AK, I would probably use it, though my first shoice would be to reload for that, too

Deltam · #17 07-31-2017, 04:16 PM

This is a little bit off the steel case topic but goes to the cost saving aspect of shooting an AR 15 for fun. I built a 9 mm AR 15 last spring and it is a hoot to shoot, using 147 gr bullets. There are commercially available 9 mm ARs out there.

vmumford · #18 07-31-2017, 04:50 PM

So If anyone out there can chime in, I have been told the same thing but with a different twist. The steel case doesn't expand like the brass there for allows the gasses to come back into the chamber and bolt group. This IMO doesn't or shouldn't be an issue if you clean your gun after every outing unless you are putting say 500-1000 rounds through it. Then I may be able to belive some extra ware. Thoughts?

ChattanoogaPhil · #19 08-02-2017, 08:29 AM

True, steel case does not expand and seal as well as brass. Generally that's not a problem shooting steel. But if you get a lot of buildup in the chamber and then start shooting brass cased ammo you may end up with a stuck case.

Arik · #20 08-02-2017, 09:02 AM

I don't over think it I just shoot. A gun is a gun. If something wears out replace it

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CBStuard · #21 08-03-2017, 05:36 PM

Quote:

Originally Posted by ChattanoogaPhil

True, steel case does not expand and seal as well as brass. Generally that's not a problem shooting steel. But if you get a lot of buildup in the chamber and then start shooting brass cased ammo you may end up with a stuck case.

This is the problem we had w/ 2 RockRiver ARs. Was a real pain. About the 4th to 5th mag of steel a case would stick. So, I carried a 3/16 brass rod about 20 inches long to shove the case out and only about 120 rnds of steel ammo. After the case stuck I would switch to brass and was 'usually' OK after that. By the time we bought a couple of S&W ARs I was off steel w/ one exception. So i can't really comment much on your Sport II, but had problems w/ another brand. BTW, MFS zinc plated steel seems to be fine. Also Wolf Gold seems to be a low price but reliable ammo.

mule69 · #22 08-09-2017, 09:13 AM

I can not afford to by a new rifle every time I shoot 6,000 rounds through it. So I do not use the stuff.

cyphertext · #23 08-09-2017, 09:41 AM

Quote:

Originally Posted by mule69

I can not afford to by a new rifle every time I shoot 6,000 rounds through it. So I do not use the stuff.

If you are buying a new rifle if you wear out an AR 15 barrel, you are doing it wrong.

If you can afford to shoot 6000 rounds, you can afford a new barrel. If you looked at the Lucky Gunner report, they showed that at 6000 rounds, shooting brass ammo, you will have spent a little over $2000. Yet shooting steel, you have spent less than $1500 and have replaced the barrel...

Arik · #24 08-09-2017, 10:04 AM

Quote:

Originally Posted by mule69

I can not afford to by a new rifle every time I shoot 6,000 rounds through it. So I do not use the stuff.

Why would you buy a new rifle? IF it's only 6k rounds then all you need is a barrel.

6 thousand rounds of steel 223 is $1326.
6 thousand rounds of cheapest brass is $1726

Difference of $402.

A good barrel will cost you less than $200.

The other thing is they were shooting none stop. The heat and constant wear is what killed the barrel. The burning of propellant, and the friction of projectiles accelerating down the barrel combine to generate considerable heat in gun chambers and barrels. The higher the rate of fire per barrel, the more heat is generated and the less time there is available for it to be dissipated.

This is why heavy machine guns have quick change barrels. Because under prolonged fire they wear out fast. A 50 caliber machine gun will have a ruined barrel in 30 seconds of sustained fire. But since they're only used in short bursts longevity is greatly extended. The much less powerful AK 47 will ruin a barrel in 1k - 2k rounds of sustained fire

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hdrolling · #25 08-09-2017, 11:35 AM

Quote:

Originally Posted by Arik

This is why heavy machine guns have quick change barrels. Because under prolonged fire they wear out fast. A 50 caliber machine gun will have a ruined barrel in 30 seconds of sustained fire. But since they're only used in short bursts longevity is greatly extended.

This in NOT why heavy machine guns have quick change barrels, they have quick change barrels because after prolonged firing there is a chance of rounds cooking off in the weapon.

shep854 · #26 08-10-2017, 08:03 PM

There are a number of videos that discuss the question. This is, IMO, the most succinct. FYI, there is some coarse language:

Arik · #27 08-10-2017, 08:23 PM

Quote:

Originally Posted by hdrolling

This in NOT why heavy machine guns have quick change barrels, they have quick change barrels because after prolonged firing there is a chance of rounds cooking off in the weapon.

And when it's that hot is the barrel still good?

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arnoob · #28 08-23-2017, 06:59 PM

Anyone else been having any problems with recent batches of Wolf WPA 62gr HP steel case 223? I've gone through about 4000 rounds of it without any issues and been very happy with it, I always scoffed at the concerns about shooting steel cased ammo, but the last two bricks (500rnd) I took to the range have had a ton of bad rounds in them, lots of FTF with clear primer strike marks but no ignition, then I had two nasty FTE cases where the case rim broke off during extraction and I ended up with an empty case stuck in the chamber. I used 3 different ARs and had the same problems in all of them. The FTF rate was ridiculous, like 10% failure rate. Some would fire on second strike, some wouldn't. Made for a *very* frustrating range session as I had a friend visiting from England and we just had no end of stoppages, and the FTE put one of my rifles out of action until I got it home.

So....I still have about 1500-1800 rounds of this stuff to shoot but I'm not sure I want the hassle of running it. Wondering if I was just unlucky with a bad batch? (I bought it in 1-2k batches, so the bad bricks could well have been from the same order). Has anyone else been seeing any issues lately with the Wolf WPA?

I have a few thousand rounds of Wolf Gold too so I'll stick to shooting that for now while I decide if I want to sell off the WPA or give it another shot, not had a single issue with the Wolf Gold but it is a little more expensive so don't really like using it for mess around slide-fire sessions.

hdrolling · #29 08-24-2017, 08:49 AM

Quote:

Originally Posted by Arik

And when it's that hot is the barrel still good?

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Yes, these barrels get switched back and forth.

For example on a 240B the cyclic rate of fire is 650 to 950 Rounds per minute fired in continuous bursts.

When doing this the barrel gets switched out every minute!

When shooting "rapid fire" which is considered 200 Rounds per minute fired in 10 to 13 round bursts and 2 to 3 seconds between bursts. Barrel change every 2 minutes.

The barrels swap back and forth that quickly and often, these barrels stay with weapons for years. Their an area weapon not meant for precision.