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Posted: 5/21/2014 4:30:52 AM EDT
| Neat article in the latest American Rifleman on the development of the new "green" round. Looks to have to some significant performance gains on standard M855. Projectile the same weight, but longer by .125 inches. Interestingly, they claim it's more accurate in a 1/9 barrel. |
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Read it as well. I'm not sure how I felt about it; the whole bit about it ONLY being accurate in 1/9 barrels seems odd, since generally speaking barrel twist doesn't effect accuracy that much as long as the round is stabilizing properly. Not like we're talking about 1/12 v. 1/7 either. I also liked the bit about "every five shot group had a flier that opened the group up larger than it should be", so they just disregard those. If you're getting that many "fliers", they're not fliers.
I dunno, the whole article seemed like a pro-M855A1 propaganda piece. |
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I am gonna crack open the article this afternoon when I get home. At this time, it does sound odd that it is touted as being more accurate in a 1/9 barrel twist barrel, when most everyone uses a 1/7 twist. I look forward to reading about it. Especially given that it's longer than M855, which does just fine in a 1/7. |
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The M855 isn't performing well enough out of our 14.5" M4's. Nevermind it was optimized for 20" barrels.
I got an idea, let's make it WAY more expensive under the guise of "going green", jack up the pressures to bring it back up to speed, and reduce the life of our current service rifles! 
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The M855 isn't performing well enough out of our 14.5" M4's. Nevermind it was optimized for 20" barrels. I got an idea, let's make it WAY more expensive under the guise of "going green", jack up the pressures to bring it back up to speed, and reduce the life of our current service rifles! http://www.automizeit.com/blog/wp-content/uploads/2012/10/guinness-brilliant.jpeg In gel, out of a 16", it looked more impressive then the $1-2 a round self defense ammo I tried. |
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In gel, out of a 16", it looked more impressive then the $1-2 a round self defense ammo I tried. Quoted:
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The M855 isn't performing well enough out of our 14.5" M4's. Nevermind it was optimized for 20" barrels. I got an idea, let's make it WAY more expensive under the guise of "going green", jack up the pressures to bring it back up to speed, and reduce the life of our current service rifles! http://www.automizeit.com/blog/wp-content/uploads/2012/10/guinness-brilliant.jpeg In gel, out of a 16", it looked more impressive then the $1-2 a round self defense ammo I tried. I recall your gel tests. What self defense round are you referring to? |
| There was another article about M855A1 in Firepower magazine I believe. Very propaganda like as well. I think the round is a waste of time and money. If the .gov wanted to go "green" they should have just gone to an all copper round. (Yes I know its not really all copper) |
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I had the same question as well. Will this be considered an AP round? 8nBAIT Quoted:
Quoted: Neat article, but wish they would have address or atleast mentioned that citizens will probably never be able to own the ammo. I had the same question as well. Will this be considered an AP round? 8nBAIT Per the ATFs legal definition is is AP because it is made entirely of steel and copper, but then again they have banned numerous rounds that arent AP even by their definition and they have also exempted rounds that are most certainly AP like the steel cored .30 cal M2 bullet. basically they will do whatever they want. My bet is it will be a LONG time before civilians can buy the new M855A1, if ever. |
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My bet is it will be a LONG time before civilians can buy the new M855A1, if ever. I'm not sure I'd ever want to buy it. Not as a complete round, anyway. Not with the high chamber pressure stories, not with the stories about how hard it is on rifles. Maybe the projectile as a component, but I really doubt it's going to wow me any more than TSX bullets. |
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The article seemed funny to me as well. I didnt get why they went with all the MOA details of the 1/7 at all these different ranges, and then say that the 1/9 was "approximately half".. how scientific.  What an inconvenient truth  Accuracy testing done by the Army using precision firing barrels in fixtures was that 95 percent of rounds hit within 8" by 8" at 600 meters |
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Accuracy testing done by the Army using precision firing barrels in fixtures was that 95 percent of rounds hit within 8" by 8" at 600 meters Quoted:
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The article seemed funny to me as well. I didnt get why they went with all the MOA details of the 1/7 at all these different ranges, and then say that the 1/9 was "approximately half".. how scientific. What an inconvenient truth Accuracy testing done by the Army using precision firing barrels in fixtures was that 95 percent of rounds hit within 8" by 8" at 600 meters Yeah I read that. It's just a lot of the wording was questionable and leaves to much in the air. The data was non existent on 1/9, just "approximately half", does this exclude the 1 in 5 flyers if they did happen in 1/9? What's approximate? +/- 0.2 MOA variation? The barrels used in 2 demonstrations was "most likely 1/8"? I read that as "I don't know but sure,ok." There's just no data but to the 1/7 for sure with flyers. It doesn't say if the other twist had flyers for sure or not. You would just think there would be more. In the end I imagine a lobbyist has the answers. Either selling barrels or trying to blame flyers on the mil spec barrel. Glad I'm stocking up copper, seems a lot is going to be thrown into the dirt. |
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When the military does Probable Error in Range/Deflection/Altitude computation they do what is know as the 10K, 95 percent rectangle. If 10k rounds are fired 95 percent will impact in the dispersion rectangle. If the dispersion rectangle is divided evenly into eight zones in range with the value for 1 probable error in range (PER) used as the unit of measure. The percentage of rounds impacting within each zone has been determined through experimentation. By definition of probable error, 50 percent of all rounds will impact within 1 probable error in range (similar in deflection) of the mean point of impact (25 percent over and 25 percent short or 25 percent left and 25 percent right).
So if at 600ms the 95 percent rectangle is 8" by civilian measurement standards it would significantly smaller. |
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http://www.americanrifleman.org/articles/testing-army-m855a1-standard-ball-cartridge
Maybe I missed it, but he didn't mention fragmentation. |
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Quoted: I am gonna crack open the article this afternoon when I get home. At this time, it does sound odd that it is touted as being more accurate in a 1/9 barrel twist barrel, when most everyone uses a 1/7 twist. I look forward to reading about it. He's saying that both M855 and M855A1 are more accurate from a 1/9 barrel and that Army reports from the 80's state that as well: "Accuracy cannot be assessed without addressing the rifle barrels’ twist-rates. In the early 1980s the M855’s 62-grain bullet was developed for the M249 Squad Automatic Weapon (SAW). For purposes of interoperability, the same load was adopted as the M16A2 rifle’s standard ball as well. A February 1986 U.S. Army study noted that the M855’s bullet required a "1:9 twist [which] would be more appropriate for the M16A2 rifle, improving accuracy and reliability.” Multiple studies confirmed the 1:9-inch twist requirement. But then a problem arose. The U.S. military’s standard M856 5.56 mm tracer round was longer, heavier (63.7 grains) and slower than the M855 ball, and simply would not stabilize with a 1:9-inch twist barrel. Thus, despite it doubling M855 group sizes, the M16A2 (and later, the M4) specified a 1:7-inch rate-of-twist barrel to stabilize the tracer round. It remains so to this day. Therefore, M855A1 was test-fired with both 1:7- and 1:9-inch twist barrels, and it was verified that this new cartridge is consistently more accurate in the latter barrels—as was its predecessor." |
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I just copied and pasted from wiki
For general issue, the U.S. Army adopted the M855A1 round in 2010 to replace the M855. The primary reason was pressure to use non-lead bullets. The lead slug is replaced by a copper alloy slug in a reverse-drawn jacket, with a hardened steel penetrator extending beyond the jacket, reducing lead contamination to the environment. The M855A1 offers several improvements other than being lead-free. It is slightly more accurate, has better consistency of effect in regards to wounding ability, and has an increased penetrating capability. The round can better penetrate steel, brick, concrete, and masonry walls, as well as body armor and sheet metal. It penetrates 3/8 in (9.5 mm) of mild steel at 350 meters, which the M855 can only do at 160 meters. The propellant burns faster, which decreases the muzzle flash and gives a higher muzzle velocity, an important feature when fired from a short barreled M4 carbine. Though the M855A1 is more expensive to produce, its performance is considered to compensate. One possible danger is that it generates much greater pressure in the chamber when fired, decreasing service life of parts, and increasing the risk of catastrophic failure of the weapon, though this has yet to occur.[35][36] The U.S. Marines adopted the Mk318 in early 2010 due to delays with the M855A1. This was a temporary measure until the M855A1 was available for them, which occurred in mid-2010 when the Army began to receive the rounds. Both the Mk318 and M855A1 weigh the same and have similar performance, and both have better performance than the M855 against all targets. SOCOM spent less money developing the Mk318 and is marginally better than the M855A1 in some situations, but costs more per round. The Army spent more developing the M855A1 which performs as well or nearly as well as the Mk318, but is cheaper per round and has the advantage of being lead-free. While SOCOM constantly looks for better equipment, the Army and Marines have far more troops to supply and buys more ammunition.[37] 
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Oh yeah, that steel tip has to be hell on the feed ramps. I can't wait to see the reports on accelerated wear on weapon systems due to this rounds adoption. With hardened Steel, even if they round it off a bit, I bet it would still do damage. Only fix I see is harder steel feedramps. |
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Great! Now the Army will spend another Gazillion $$ developing a super polished Inconel barrel extension.
The trick with Maj. Plaster articles is to read between the lines. It was interesting that the 1:7" twist came about to accommodate the new extra-long tracer that replaced a perfectly useable tracer. Tail wagging the dog, big time. The Army doing its demonstrations using hand made target rifles is like the M110 acquisition process. There they used Geissele triggers for the demonstration units, but went to KAC crapola triggers for the issue rifles. The one good thing to come out of this (it seems) is that in late 2008 or early 2009 everyone involved in the project was told that if they did not get the job done, and fast, they would all be looking for new jobs. Voila, less than a year later and they produce the new bullet. Nothing like a blowtorch against a bare rear end to speed up the R&D process. I have my doubts about accuracy of this new round regardless of the twist. These are not Palma rifles, so I would like to see some head to head competition. I think the demonstration shooting went well mainly because they used MATCH rifles. If the accuracy is not there with issue rifles, then the accuracy does not exist, and the round fails the accuracy requirement. Period. Rant over. |
| Colt uses a 70k PSI proof load to test the barrel and bolt. The M855A1 raises the average pressure from 55k PSI to 62k+ PSI. I am not at all enthused about how much harder this new round is going to work the rifle and would expect parts longevities to be at least halved. |
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The article mentioned that yaw began in soft tissue targets at 1 inch. Yes with a solid copper slug I'm betting fragmentation is about zero. Perhaps the steel tip will separate from the copper slug and we will get two wound paths... But otherwise it looks like bullet yaw will be the primary wounding mechanism.
Kinda like the 5.45x39. |
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Knifesniper,
i think the wounding mechanism of the A1 is due to the disintigration of the sintered (compressed powder) "core" material behind the steel ogive. the steel is over twice weight of M855 green tip penetrator, a good thing for barricades which require some mass to perforate. It is a three peice bullet, all of which go their separate ways in gelatin I would bet. The sintered core, whether it is copper or bismith is why the army says it is not yaw dependant. |
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Knifesniper, i think the wounding mechanism of the A1 is due to the disintigration of the sintered (compressed powder) "core" material behind the steel ogive. the steel is over twice weight of M855 green tip penetrator, a good thing for barricades which require some mass to perforate. It is a three peice bullet, all of which go their separate ways in gelatin I would bet. The sintered core, whether it is copper or bismith is why the army says it is not yaw dependant. There is no compressed powder |
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Infintie Grim,
I see that I am out of date! I see the bismuth-tin alloy was replaced with a solid copper slug. Dont know how it is not yaw dependant now? This from Wikipedia. The M855A1 was put on hold in August 2009 due to the experimental bismuth-tin alloy core exhibiting undependable ballistics at high temperatures. The US Army has since replaced the bismuth-tin alloy core with one of solid copper eliminating the heat issue. The United States Marine Corps purchased 1.8 million rounds in 2010, with plans to adopt the round to replace the interim MK318 SOST rounds used in Afghanistan when the M855A1 project was delayed.[80] Maybe the "solid copper" slug is sintered? Fragmentation must depend on the penetrator driving through the copper core, breaking it up, like the old Remington Bronze point did. Anyone know, or are photos of gelatin shots still semi classified? |
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That was the feeling I got. Quoted:
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I dunno, the whole article seemed like a pro-M855A1 propaganda piece. That was the feeling I got. Same here. I quickly disregarded the article after I got the feeling they were trying to sell it to me. Just progressive steps to desensitize us to the attack on lead bullets to come. what is wrong with the MK318? |
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Infintie Grim, I see that I am out of date! I see the bismuth-tin alloy was replaced with a solid copper slug. Dont know how it is not yaw dependant now? This from Wikipedia. The M855A1 was put on hold in August 2009 due to the experimental bismuth-tin alloy core exhibiting undependable ballistics at high temperatures. The US Army has since replaced the bismuth-tin alloy core with one of solid copper eliminating the heat issue. The United States Marine Corps purchased 1.8 million rounds in 2010, with plans to adopt the round to replace the interim MK318 SOST rounds used in Afghanistan when the M855A1 project was delayed.[80] Maybe the "solid copper" slug is sintered? Fragmentation must depend on the penetrator driving through the copper core, breaking it up, like the old Remington Bronze point did. Anyone know, or are photos of gelatin shots still semi classified? The M855A1 procured the Marine Corps was for testing and evaluation; we have never operationally deployed the round. |
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Same here. I quickly disregarded the article after I got the feeling they were trying to sell it to me. Just progressive steps to desensitize us to the attack on lead bullets to come. what is wrong with the MK318? Quoted:
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I dunno, the whole article seemed like a pro-M855A1 propaganda piece. That was the feeling I got. Same here. I quickly disregarded the article after I got the feeling they were trying to sell it to me. Just progressive steps to desensitize us to the attack on lead bullets to come. what is wrong with the MK318? Apparently, the major flaw with it is that it's not "green". 
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| I'm not a "green" fanatic. But I am a strong believer in true monolithic copper bullets (not this steel insert penetrstor). I have just about across the board moved to Barnes TSX and TTSX bullets for hunting in all my bolt guns and for tactical use in my AR because of the better ballistic cooefficient for comparable weight and superior terminal performance. That they happen to be lead free is incidental to me. |
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I'm not a "green" fanatic. But I am a strong believer in true monolithic copper bullets (not this steel insert penetrstor). I have just about across the board moved to Barnes TSX and TTSX bullets for hunting in all my bolt guns and for tactical use in my AR because of the better ballistic cooefficient for comparable weight and superior terminal performance. That they happen to be lead free is incidental to me. Copper is Great for hunting... Maybe not so great for a military round that includes machine guns, barrel life, and barrier penetration as some key considerations? |
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Copper is Great for hunting... Maybe not so great for a military round that includes machine guns, barrel life, and barrier penetration as some key considerations? Quoted:
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I'm not a "green" fanatic. But I am a strong believer in true monolithic copper bullets (not this steel insert penetrstor). I have just about across the board moved to Barnes TSX and TTSX bullets for hunting in all my bolt guns and for tactical use in my AR because of the better ballistic cooefficient for comparable weight and superior terminal performance. That they happen to be lead free is incidental to me. Copper is Great for hunting... Maybe not so great for a military round that includes machine guns, barrel life, and barrier penetration as some key considerations? I agree that barrel life may go down. Perhaps nitro-carburizing (nitrite) might be better for barrel life than chrome lining of the barrel interior. In theory it is. But, for barrier penetration, I think the Barnes TSX civilian ammo did very well in the FBI barrier tests and is highly recommended because of its penetration and terminal ballistics. A copper monolithic service round should be far superior to lead core bullets. In hunting bullets, I now deliberately shoot to break the shoulder on game rather than just behind, and the bullet still typically produces an exit wound. I know Geneva Convention protocols (as silly and out of date as they are) do not permit expanding bullets, but still, copper monolithic has an advantage and can be designed to tumble. |
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I agree that barrel life may go down. Perhaps nitro-carburizing (nitrite) might be better for barrel life than chrome lining of the barrel interior. In theory it is. But, for barrier penetration, I think the Barnes TSX civilian ammo did very well in the FBI barrier tests and is highly recommended because of its penetration and terminal ballistics. A copper monolithic service round should be far superior to lead core bullets. In hunting bullets, I now deliberately shoot to break the shoulder on game rather than just behind, and the bullet still typically produces an exit wound. I know Geneva Convention protocols (as silly and out of date as they are) do not permit expanding bullets, but still, copper monolithic has an advantage and can be designed to tumble. Quoted:
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I'm not a "green" fanatic. But I am a strong believer in true monolithic copper bullets (not this steel insert penetrstor). I have just about across the board moved to Barnes TSX and TTSX bullets for hunting in all my bolt guns and for tactical use in my AR because of the better ballistic cooefficient for comparable weight and superior terminal performance. That they happen to be lead free is incidental to me. Copper is Great for hunting... Maybe not so great for a military round that includes machine guns, barrel life, and barrier penetration as some key considerations? I agree that barrel life may go down. Perhaps nitro-carburizing (nitrite) might be better for barrel life than chrome lining of the barrel interior. In theory it is. But, for barrier penetration, I think the Barnes TSX civilian ammo did very well in the FBI barrier tests and is highly recommended because of its penetration and terminal ballistics. A copper monolithic service round should be far superior to lead core bullets. In hunting bullets, I now deliberately shoot to break the shoulder on game rather than just behind, and the bullet still typically produces an exit wound. I know Geneva Convention protocols (as silly and out of date as they are) do not permit expanding bullets, but still, copper monolithic has an advantage and can be designed to tumble. Hague Convention, not Geneva. |
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Hague Convention, not Geneva. Quoted:
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I'm not a "green" fanatic. But I am a strong believer in true monolithic copper bullets (not this steel insert penetrstor). I have just about across the board moved to Barnes TSX and TTSX bullets for hunting in all my bolt guns and for tactical use in my AR because of the better ballistic cooefficient for comparable weight and superior terminal performance. That they happen to be lead free is incidental to me. Copper is Great for hunting... Maybe not so great for a military round that includes machine guns, barrel life, and barrier penetration as some key considerations? I agree that barrel life may go down. Perhaps nitro-carburizing (nitrite) might be better for barrel life than chrome lining of the barrel interior. In theory it is. But, for barrier penetration, I think the Barnes TSX civilian ammo did very well in the FBI barrier tests and is highly recommended because of its penetration and terminal ballistics. A copper monolithic service round should be far superior to lead core bullets. In hunting bullets, I now deliberately shoot to break the shoulder on game rather than just behind, and the bullet still typically produces an exit wound. I know Geneva Convention protocols (as silly and out of date as they are) do not permit expanding bullets, but still, copper monolithic has an advantage and can be designed to tumble. Hague Convention, not Geneva. Right! My bad. |
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