obviously not mine but a great article
http://www.luckygunner.com/labs/brass-vs-steel-cased-ammo/#reliable
http://www.luckygunner.com/labs/brass-vs-steel-cased-ammo/#reliable
brass vs. steel case a great review
- Thread starter 1shot2kill
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Re: brass vs. steel case a great review
Kind of shows what we've always known. There is a reason why some ammunition is more expensive than others.
Kind of shows what we've always known. There is a reason why some ammunition is more expensive than others.
Re: brass vs. steel case a great review
Honestly, that's not what I take away from this.
A) Firstly, the deliberate minimalist attention to maintenance would never be occurring with any rifle of my own. I firmly believe that better attention to care and cleaning would have probably reduced malfunctions. The numbers of steelcased malfunctions (I.e 0.09% of the rounds fired) is more than 0.0%, granted, but hardly a screaming indictment against steelcased ammo.
B) Simply put, if I'm shooting a match, I'm shooting handloads. Other than that, I'm using bulk ammo, and price <span style="font-style: italic">and availability</span> play decisive roles in my purchasing of bulk ammo. My sources have (had?) far more steelcase ammo available than brass cased. I think the retail prices of the various brands/types played some role in their availability; the dealers probably (and maybe correctly) assumed that they would sell less of a higher priced product, and ordered accordingly.
C) For all practical intents and purposes, the bulk of the malfunctions occurred so far into the lifespan of the rifles that the odds favor my (and maybe most of the others here) never reaching that stage in their AR's lives. Assuming further that I would never have cleaned or maintained my rifle at the 3000 round mark is patently impossible.
D) I suspect that the bushmaster Carbine's bore length and gas port dimensions are critical to the malfunctions encountered, the report as much as says so. The system was originally designed around a different (longer) bore length, and the report's conclusion that a larger (more conventional?) bore gas port diameter would have essentially resolved/eliminated cycling issues.
E) The observations that steel cases expand and contract differently are highly valid, but not much correlation between that and the malfunctions appears to me to have any emphasis in the final conclusions.
F) I personally believe the assessment about case coatings not playing a significant role in malfunction is very telling to me. I think this report puts that myth into its coffin for once and all, precisely where it belongs.
G) The bimetal jackets correspond to very disturbing bore wear at the 10000 round mark; and no such correlation appears with the copper jackets. If I ever reach even half as many rounds down my bore, I may have to give this issue some actual serious thought.
I think its a good report. I can use what steelcased ammo I have with a clear conscience.
Greg
Honestly, that's not what I take away from this.
A) Firstly, the deliberate minimalist attention to maintenance would never be occurring with any rifle of my own. I firmly believe that better attention to care and cleaning would have probably reduced malfunctions. The numbers of steelcased malfunctions (I.e 0.09% of the rounds fired) is more than 0.0%, granted, but hardly a screaming indictment against steelcased ammo.
B) Simply put, if I'm shooting a match, I'm shooting handloads. Other than that, I'm using bulk ammo, and price <span style="font-style: italic">and availability</span> play decisive roles in my purchasing of bulk ammo. My sources have (had?) far more steelcase ammo available than brass cased. I think the retail prices of the various brands/types played some role in their availability; the dealers probably (and maybe correctly) assumed that they would sell less of a higher priced product, and ordered accordingly.
C) For all practical intents and purposes, the bulk of the malfunctions occurred so far into the lifespan of the rifles that the odds favor my (and maybe most of the others here) never reaching that stage in their AR's lives. Assuming further that I would never have cleaned or maintained my rifle at the 3000 round mark is patently impossible.
D) I suspect that the bushmaster Carbine's bore length and gas port dimensions are critical to the malfunctions encountered, the report as much as says so. The system was originally designed around a different (longer) bore length, and the report's conclusion that a larger (more conventional?) bore gas port diameter would have essentially resolved/eliminated cycling issues.
E) The observations that steel cases expand and contract differently are highly valid, but not much correlation between that and the malfunctions appears to me to have any emphasis in the final conclusions.
F) I personally believe the assessment about case coatings not playing a significant role in malfunction is very telling to me. I think this report puts that myth into its coffin for once and all, precisely where it belongs.
G) The bimetal jackets correspond to very disturbing bore wear at the 10000 round mark; and no such correlation appears with the copper jackets. If I ever reach even half as many rounds down my bore, I may have to give this issue some actual serious thought.
I think its a good report. I can use what steelcased ammo I have with a clear conscience.
Greg
Re: brass vs. steel case a great review
Bushmaster is very, very inconsistent with where they get parts and what their specs are. I find it hard to believe that they had such a small gas port diameter as they usually are LARGER in order to cycle commercial bulk ammo that tends to use very fast burning powders (which I may suspect is because faster powders get more velocity with a smaller charge---thus less charge=less powder=less expense). The author is also wrong in that Colt 6920s have a .063" gas port diameter rather than the .058". That's nearly 9%!!! I believe, the 14.5" barrel is what the .063" was designed for. Therefore .063" ported 16" guns are often approaching the "over-gassed" side of things. I run an H2 in my 16" with a .063".
Shouldn't one also be looking at other aspects to the system such as chamber dimensions, carrier mass, etc?
Another idea the author may explore is that he believed the wear to be a result of the jacket of the bullet. Did he account for the barrel material? For instance a Bushmaster uses 4140 steel, while Spikes claims to use 4150 CMV, and Colt uses MIL-B-11595E. Additionally, the faster burning powders of the budget rounds WILL burn a throat faster. It may not be the jacket after all. More testing would need done to make such a conclusion.
Also, I don't recall any mention of different extractor/spring/insert combos on the rifles he used. That could also play a role.
Overall, its a good write up and it demonstrates why people need to use good ammunition, as well as quality firearms.
Bushmaster is very, very inconsistent with where they get parts and what their specs are. I find it hard to believe that they had such a small gas port diameter as they usually are LARGER in order to cycle commercial bulk ammo that tends to use very fast burning powders (which I may suspect is because faster powders get more velocity with a smaller charge---thus less charge=less powder=less expense). The author is also wrong in that Colt 6920s have a .063" gas port diameter rather than the .058". That's nearly 9%!!! I believe, the 14.5" barrel is what the .063" was designed for. Therefore .063" ported 16" guns are often approaching the "over-gassed" side of things. I run an H2 in my 16" with a .063".
Shouldn't one also be looking at other aspects to the system such as chamber dimensions, carrier mass, etc?
Another idea the author may explore is that he believed the wear to be a result of the jacket of the bullet. Did he account for the barrel material? For instance a Bushmaster uses 4140 steel, while Spikes claims to use 4150 CMV, and Colt uses MIL-B-11595E. Additionally, the faster burning powders of the budget rounds WILL burn a throat faster. It may not be the jacket after all. More testing would need done to make such a conclusion.
Also, I don't recall any mention of different extractor/spring/insert combos on the rifles he used. That could also play a role.
Overall, its a good write up and it demonstrates why people need to use good ammunition, as well as quality firearms.
Re: brass vs. steel case a great review
Tyler, you may need to re-read the article. He specified the rifle model, and if you google that particular model's spec chart you'll find the barrels are of 4150 and both bores and chambers are chrome-lined.
Gas port diameter will vary by manufacturer. Colt specifies a number of different gas port dimensions (specifically for true military 20-inch M16, 14.5-inch M4, and 12.5-inch Commando). The 16-inch commercial carbine may or may not have the same port dimensions as shorter and longer barrels.
This was a single, well-done test. As noted by others' pointing out it may or may not jibe with their findings. Go from this start point, test, document, and prove or disprove the guy's research.
Easier and cheaper to sharp-shoot others' work than to actually make the investment to prove or disprove.
Tyler, you may need to re-read the article. He specified the rifle model, and if you google that particular model's spec chart you'll find the barrels are of 4150 and both bores and chambers are chrome-lined.
Gas port diameter will vary by manufacturer. Colt specifies a number of different gas port dimensions (specifically for true military 20-inch M16, 14.5-inch M4, and 12.5-inch Commando). The 16-inch commercial carbine may or may not have the same port dimensions as shorter and longer barrels.
This was a single, well-done test. As noted by others' pointing out it may or may not jibe with their findings. Go from this start point, test, document, and prove or disprove the guy's research.
Easier and cheaper to sharp-shoot others' work than to actually make the investment to prove or disprove.
Re: brass vs. steel case a great review
Sinister, he left it vague on the replacements:
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">
The carbine firing Tula had a case stuck in the chamber after 189 rounds which proved exceptionally difficult to clear, even with the use of a steel cleaning rod after the rifle had cooled. Over the next three hundred rounds, 24 malfunctions – stuck cases and failures to fully cycle, or “short stroking” – were encountered. At this time, the Tula carbine was removed from the testing, as the problems were causing significant delays.
A decision was made to fire the remainder of the Tula ammunition through other carbines. Approximately 300 rounds were fired through an HK416 (no malfunctions), 1,000 through a Spike’s Tactical carbine (3 malfunctions), and 6,000 through a Spike’s Tactical midlength without any cleaning (3 malfunctions). All malfunctions with the other carbines were stuck cases or failures to eject.</div></div>
I was simply pointing out some potential explanations and further questions, which is normal for any test. People don't just take a test as "gospel".
You're right, Bushmaster's chart says its 4150, but I've seen far to many that aren't; frequently stamped 4140. I still want to know if he measured the gas port diameter and where he measured Colt diameters at .058" as well.
Here's the numbers I've consistently found published:
10.5" .093"
11.5" .081"
14" .063"
16" .063"
20" .093"
Where did I say it was a poorly done test that needs "disproved and discredited"? I simply said that before drawing conclusions, more things need looked at. I said "its a good write up and it demonstrates why people need to use good ammunition, as well as quality firearms." Or did you need to reread my post?
Sinister, he left it vague on the replacements:
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">
The carbine firing Tula had a case stuck in the chamber after 189 rounds which proved exceptionally difficult to clear, even with the use of a steel cleaning rod after the rifle had cooled. Over the next three hundred rounds, 24 malfunctions – stuck cases and failures to fully cycle, or “short stroking” – were encountered. At this time, the Tula carbine was removed from the testing, as the problems were causing significant delays.
A decision was made to fire the remainder of the Tula ammunition through other carbines. Approximately 300 rounds were fired through an HK416 (no malfunctions), 1,000 through a Spike’s Tactical carbine (3 malfunctions), and 6,000 through a Spike’s Tactical midlength without any cleaning (3 malfunctions). All malfunctions with the other carbines were stuck cases or failures to eject.</div></div>
I was simply pointing out some potential explanations and further questions, which is normal for any test. People don't just take a test as "gospel".
You're right, Bushmaster's chart says its 4150, but I've seen far to many that aren't; frequently stamped 4140. I still want to know if he measured the gas port diameter and where he measured Colt diameters at .058" as well.
Here's the numbers I've consistently found published:
10.5" .093"
11.5" .081"
14" .063"
16" .063"
20" .093"
Where did I say it was a poorly done test that needs "disproved and discredited"? I simply said that before drawing conclusions, more things need looked at. I said "its a good write up and it demonstrates why people need to use good ammunition, as well as quality firearms." Or did you need to reread my post?
Re: brass vs. steel case a great review
Point taken, and as you are from the "Show Me" state have you confirmed the published port numbers you've found?
Certainly other manufacturers use their own numbers, so Remington-Bushamster may have their own, so again you're correct.
Point taken, and as you are from the "Show Me" state have you confirmed the published port numbers you've found?
Certainly other manufacturers use their own numbers, so Remington-Bushamster may have their own, so again you're correct.
Re: brass vs. steel case a great review
Most of the research I've done was in 2007-2009, but I'm sure I can dig some of it up for you if you want to wait around a few days. I can say the RRA, Bushmaster, DPMS, and other Wilson barrels I've measured had VERY large gas ports from .070-.10"---there's literally no consistency, or at least wasn't then, with the dozen or so I messed with. The Colt, Daniel Defense, and BCM barrels I've measured were in the 0.060-.064" range with my primitive measuring. I even e-mailed a few manufacturers to get what they claim to be their numbers and it was close to my primitive measuring. No, I didn't publish it anywhere. And yes, you can tell a difference. The recoil feels different, you get varying degrees of muzzle rise, and ejection patterns are very different given other parts are the same. Sometimes the bulk loads simply won't function reliably in guns with smaller gas port diameters.
Moral of the story, something was seriously wrong with Bushmaster QC if they let one squeak out at .058". It seems odd most of the stuff ran as well as it did in that gun, though I've never shot them with the light bolt carriers (the "semi-auto" carriers, not sure why one would call them that, honestly) and they didn't mention what buffers they were running either. My 14.5" DD middy will just barely run Tula or Wolf, so long as its sopping wet with the lightest buffer I own.
ETA:
Here's a quick google hit for a guy to read if you'd like:
http://vuurwapenblog.com/2010/05/19/beyond-the-chart-factors-affecting-ar-15-reliability/
http://www.m4carbine.net/showthread.php?t=33550
Most of the research I've done was in 2007-2009, but I'm sure I can dig some of it up for you if you want to wait around a few days. I can say the RRA, Bushmaster, DPMS, and other Wilson barrels I've measured had VERY large gas ports from .070-.10"---there's literally no consistency, or at least wasn't then, with the dozen or so I messed with. The Colt, Daniel Defense, and BCM barrels I've measured were in the 0.060-.064" range with my primitive measuring. I even e-mailed a few manufacturers to get what they claim to be their numbers and it was close to my primitive measuring. No, I didn't publish it anywhere. And yes, you can tell a difference. The recoil feels different, you get varying degrees of muzzle rise, and ejection patterns are very different given other parts are the same. Sometimes the bulk loads simply won't function reliably in guns with smaller gas port diameters.
Moral of the story, something was seriously wrong with Bushmaster QC if they let one squeak out at .058". It seems odd most of the stuff ran as well as it did in that gun, though I've never shot them with the light bolt carriers (the "semi-auto" carriers, not sure why one would call them that, honestly) and they didn't mention what buffers they were running either. My 14.5" DD middy will just barely run Tula or Wolf, so long as its sopping wet with the lightest buffer I own.
ETA:
Here's a quick google hit for a guy to read if you'd like:
http://vuurwapenblog.com/2010/05/19/beyond-the-chart-factors-affecting-ar-15-reliability/
http://www.m4carbine.net/showthread.php?t=33550
Re: brass vs. steel case a great review
There was an article in 'Front Sight' last year where they used a high power microscope to look at bi-metal bullets after they were shot and it showed the rifling going through the copper wash in to the steel jacket. This test proves what they found. I will never use steel case in my stainless barrels but will continue you to do so in my chrome-lined carbines since my usual range round count is around 175 rounds with no mag dumps. I would like to see if the barrels would survive past the 6,000 rounds if a more realistic (range trip, carbine class)round count was kept..Very informative test!!
There was an article in 'Front Sight' last year where they used a high power microscope to look at bi-metal bullets after they were shot and it showed the rifling going through the copper wash in to the steel jacket. This test proves what they found. I will never use steel case in my stainless barrels but will continue you to do so in my chrome-lined carbines since my usual range round count is around 175 rounds with no mag dumps. I would like to see if the barrels would survive past the 6,000 rounds if a more realistic (range trip, carbine class)round count was kept..Very informative test!!
Re: brass vs. steel case a great review
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: tylerw02</div><div class="ubbcode-body">
Here's a quick google hit for a guy to read if you'd like:
http://vuurwapenblog.com/2010/05/19/beyond-the-chart-factors-affecting-ar-15-reliability/
</div></div>
Andrew Tuohy (aka 87GN and vuurwapen) is the guy who did the Lucky Gunner test cited at the top.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: tylerw02</div><div class="ubbcode-body">
Here's a quick google hit for a guy to read if you'd like:
http://vuurwapenblog.com/2010/05/19/beyond-the-chart-factors-affecting-ar-15-reliability/
</div></div>
Andrew Tuohy (aka 87GN and vuurwapen) is the guy who did the Lucky Gunner test cited at the top.
Re: brass vs. steel case a great review
So in other words he knows there's more to it, but didn't include it. He should know that Colts aren't .058". That's why other people look at your work and ask questions
So in other words he knows there's more to it, but didn't include it. He should know that Colts aren't .058". That's why other people look at your work and ask questions
Re: brass vs. steel case a great review
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: danish1911</div><div class="ubbcode-body">There was an article in 'Front Sight' last year where they used a high power microscope to look at bi-metal bullets after they were shot and it showed the rifling going through the copper wash in to the steel jacket. This test proves what they found. I will never use steel case in my stainless barrels but will continue you to do so in my chrome-lined carbines since my usual range round count is around 175 rounds with no mag dumps. I would like to see if the barrels would survive past the 6,000 rounds if a more realistic (range trip, carbine class)round count was kept..Very informative test!! </div></div>
What about Hornady's steel case? That seems to be completely fine--cheap SPR food.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: danish1911</div><div class="ubbcode-body">There was an article in 'Front Sight' last year where they used a high power microscope to look at bi-metal bullets after they were shot and it showed the rifling going through the copper wash in to the steel jacket. This test proves what they found. I will never use steel case in my stainless barrels but will continue you to do so in my chrome-lined carbines since my usual range round count is around 175 rounds with no mag dumps. I would like to see if the barrels would survive past the 6,000 rounds if a more realistic (range trip, carbine class)round count was kept..Very informative test!! </div></div>
What about Hornady's steel case? That seems to be completely fine--cheap SPR food.
Re: brass vs. steel case a great review
Hornady is fine. It's just a steel case with copper/lead bullet. I've shot a fair amount of it and wish I could find more..
Hornady is fine. It's just a steel case with copper/lead bullet. I've shot a fair amount of it and wish I could find more..
