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Optimum 6.5 Grendel bullet weights - stanc - 08-18-2011
Tony Williams Wrote:Incidentally, I keep coming across reference to the "brown tip" 5.56mm ammo but no details.Perhaps this would be a good question for the iaaforum?
Does it have a SOCOM MK number, like the MK262?
Optimum 6.5 Grendel bullet weights - JASmith - 08-18-2011
stanc Wrote:You've lost me, Joe. I've no idea what you're talking about now, and you're going all over the place with subjects that have no bearing on the discussion.
Or are you just reverting to your propensity for trying to make things far more complicated and difficult than they really are? :confused:
I am trying to get this discussion grounded in reality rather than wishful thinking. Things are indeed more complicated and difficult than many would like to think.
Optimum 6.5 Grendel bullet weights - stanc - 08-18-2011
Tony Williams Wrote:I think that the only chance an intermediate round will have of being adopted by the military is if it is able to replace 7.62mm as well as 5.56mm, since that would provide significant advantages (especially ammo weight reduction).While it would clearly provide a significant weight reduction for machine gunners, it'd mean a weight increase for riflemen. Not only would the ammo be at least 50% heavier than 5.56mm, it would (for US troops) likely necessitate a switch from lightweight aluminum magazines to heavier steel mags, further increasing the carry load. And it'd require a bigger, heavier rifle, too.
Quote:It is clear that the US Army wants lead-free ammo in the future and that the M855A1 EPR represents the currently favoured pattern so, whatever bullet weight is selected, the design should comply with this.Concur.
Quote:I am not overly concerned with bullet weight as such, more with the ballistic coefficient. At the very least the BC should match the M80, which would mean that the muzzle velocity would have to do the same to match the long-range ballistics. Obviously, the better the BC, the more the MV could fall while still matching the M80 at long range. However, too low an MV could cause trajectory issues at short to medium ranges, so is not desirable.Precisely.
As ever, there will not be one universally-agreed "right" solution to this conundrum, it's a matter of juggling various criteria to get the optimum compromise.
Optimum 6.5 Grendel bullet weights - stanc - 08-18-2011
JASmith Wrote:I am trying to get this discussion grounded in reality rather than wishful thinking.Well, I'm all for being grounded in reality. So please. Enlighten me. What, in your learned opinion, has been "wishful thinking" in my posts? Inquiring minds want to know.
Quote:Things are indeed more complicated and difficult than many would like to think.Perhaps. But things are in fact seldom as complicated and difficult as you like to make them out to be.
Optimum 6.5 Grendel bullet weights - Variable - 08-18-2011
stanc Wrote:And it'd require a bigger, heavier rifle, too.Hunh???
Optimum 6.5 Grendel bullet weights - Tony Williams - 08-18-2011
stanc Wrote:Perhaps this would be a good question for the iaaforum?
Done, thanks!
Quote:While it would clearly provide a significant weight reduction for machine gunners, it'd mean a weight increase for riflemen. Not only would the ammo be at least 50% heavier than 5.56mm, it would (for US troops) likely necessitate a switch from lightweight aluminum magazines to heavier steel mags, further increasing the carry load. And it'd require a bigger, heavier rifle, too.It would result in an ammo weight increase for riflemen used to carrying 5.56mm, yes, but there has been some interesting feedback from the Royal Marines on their use of rifles. They have commented that troops are far readier to use up large quantities of 5.56mm ammo, while the 7.62mm riflemen pick their targets so get through far less ammo. This may in part be because it's the better riflemen who are given 7.62mm guns, but I suspect that a harder-hitting, longer-ranged intermediate round would encourage more careful shooting.
I doubt that a rifle in an intermediate calibre would weigh any more than the L85A2!
Optimum 6.5 Grendel bullet weights - JASmith - 08-18-2011
stanc Wrote:Well, I'm all for being grounded in reality. So please. Enlighten me. What, in your learned opinion, has been "wishful thinking" in my posts? Inquiring minds want to know.
Perhaps. But things are in fact seldom as complicated and difficult as you like to make them out to be.
Oh well...one can lead horses to water, but one can't force them to drink.
Optimum 6.5 Grendel bullet weights - stanc - 08-18-2011
Variable Wrote:Hunh???Tony's proposed, intermediate-length cartridge would require a rifle receiver longer than that for 5.56mm.
Longer receiver = heavier, bigger.
Optimum 6.5 Grendel bullet weights - stanc - 08-18-2011
Tony Williams Wrote:It would result in an ammo weight increase for riflemen used to carrying 5.56mm, yes, but there has been some interesting feedback from the Royal Marines on their use of rifles. They have commented that troops are far readier to use up large quantities of 5.56mm ammo, while the 7.62mm riflemen pick their targets so get through far less ammo. This may in part be because it's the better riflemen who are given 7.62mm guns, but I suspect that a harder-hitting, longer-ranged intermediate round would encourage more careful shooting.That could well be.
Quote:I doubt that a rifle in an intermediate calibre would weigh any more than the L85A2!Unless they stick with the L85 design and "stretch" it to fit the new round! :eek:
Optimum 6.5 Grendel bullet weights - LR1955 - 08-18-2011
Tony Williams Wrote:Done, thanks!
It would result in an ammo weight increase for riflemen used to carrying 5.56mm, yes, but there has been some interesting feedback from the Royal Marines on their use of rifles. They have commented that troops are far readier to use up large quantities of 5.56mm ammo, while the 7.62mm riflemen pick their targets so get through far less ammo. This may in part be because it's the better riflemen who are given 7.62mm guns, but I suspect that a harder-hitting, longer-ranged intermediate round would encourage more careful shooting.
I doubt that a rifle in an intermediate calibre would weigh any more than the L85A2!
Tony:
More than likely it is because the recoil is so much greater that it knocks the shooter out of his position and thus takes longer for follow on shots. And, the recoil does fatigue shooters and causes flinching so shooters are less inclined to shoot more ammo.
Hit probability will always be higher with a lighter recoiling rifle because of less recoil, and less overpressure bothering the shooter. Follow on shots will be more precise as well and gaining fire superiority will go with those who can shoot more ammo, more accurately, faster.
LR1955
Optimum 6.5 Grendel bullet weights - RangerRick - 08-18-2011
stanc Wrote:Why would that be "more meaningful"??? In CQB, how often is there a barrier between shooter and target?
Why be concerned at all about sectional density? Isn't maximizing (or optimizing) terminal effects what should be important?
In CQB often you are clearing a building so you want to be able to shoot through a wall to get the guy. Also stair wells are a pain to clear. If you can shoot up through the step above you and hit the guy hanging over the rail hosing you down, that's a plus.
More and more bad guys are showing up with body armor, too.
Two Marines got the Navy Cross for stopping a truck bomber in Iraq. The engagement lasted 6 seconds. They both died. Who knows, maybe better barrier penetration and post barrier effects could have stopped the truck sooner. Read what their commander said:
On Nov 13, 2010 Lt General John Kelly, USMC gave a speech to the Semper Fi Society of St. Louis, MO. This was 4 days after his son, Lt Robert Kelly, USMC was killed by an IED while on his 3rd Combat tour. During his speech, General Kelly spoke about the dedication and valor of the young men and women who step forward each and every day to protect us. During the speech, he never mentioned the loss of his own son. He closed the speech with the moving account of the last 6 seconds in the lives of 2 young Marines who died with rifles blazing to protect their brother Marines.
"I will leave you with a story about the kind of people they are.about the quality of the steel in their backs.about the kind of dedication they bring to our country while they serve in uniform and forever after as veterans.
Two years ago when I was the Commander of all U.S. and Iraqi forces, in fact, the 22nd of April 2008, two Marine infantry battalions, 1/9 "The Walking Dead," and 2/8 were switching out in Ramadi. One battalion in the closing days of their deployment going home very soon, the other just starting its seven-month combat tour. Two Marines, Corporal Jonathan Yale and Lance Corporal Jordan Haerter, 22 and 20 years old respectively, one from each battalion, were assuming the watch together at the entrance gate of an outpost that contained a makeshift barracks housing 50 Marines. The same broken down ramshackle building was also home to 100 Iraqi police, also my men and our allies in the fight against the terrorists in Ramadi, a city until recently the most dangerous city on earth and owned by Al Qaeda.
Yale was a dirt poor mixed-race kid from Virginia with a wife and daughter, and a mother and sister who lived with him and he supported as well. He did this on a yearly salary of less than $23,000. Haerter, on the other hand, was a middle class white kid from Long Island. They were from two completely different worlds. Had they not joined the Marines they would never have met each other, or understood that multiple America's exist simultaneously depending on one's race, education level, economic status, and where you might have been born. But they were Marines, combat Marines, forged in the same crucible of Marine training, and because of this bond they were brothers as close, or closer, than if they were born of the same woman.
The mission orders they received from the sergeant squad leader I am sure went something like: "Okay you two clowns, stand this post and let no unauthorized personnel or vehicles pass." "You clear?" I am also sure Yale and Haerter then rolled their eyes and said in unison something like:
"Yes Sergeant," with just enough attitude that made the point without saying the words, "No kidding sweetheart, we know what we're doing." They then relieved two other Marines on watch and took up their post at the entry control point of Joint Security Station Nasser, in the Sophia section of Ramadi, Al Anbar, Iraq.
A few minutes later a large blue truck turned down the alley way-perhaps 60-70 yards in length-and sped its way through the serpentine of concrete jersey walls. The truck stopped just short of where the two were posted and detonated, killing them both catastrophically. Twenty-four brick masonry houses were damaged or destroyed. A mosque 100 yards away collapsed. The truck's engine came to rest two hundred yards away knocking most of a house down before it stopped. Our explosive experts reckoned the blast was made of 2,000 pounds of explosives. Two died, and because these two young infantrymen didn't have it in their DNA to run from danger, they saved 150 of their Iraqi and American brothers-in-arms.
When I read the situation report about the incident a few hours after it happened I called the regimental commander for details as something about this struck me as different. Marines dying or being seriously wounded is commonplace in combat. We expect Marines regardless of rank or MOS to stand their ground and do their duty, and even die in the process, if that is what the mission takes. But this just seemed different. The regimental commander had just returned from the site and he agreed, but reported that there were no American witnesses to the event-just Iraqi police. I figured if there was any chance of finding out what actually happened and then to decorate the two Marines to acknowledge their bravery, I'd have to do it as a combat award that requires two eye-witnesses and we figured the bureaucrats back in Washington would never buy Iraqi statements. If it had any chance at all, it had to come under the signature of a general officer.
I traveled to Ramadi the next day and spoke individually to a half-dozen Iraqi police all of whom told the same story. The blue truck turned down into the alley and immediately sped up as it made its way through the serpentine. They all said, "We knew immediately what was going on as soon as the two Marines began firing." The Iraqi police then related that some of them also fired, and then to a man, ran for safety just prior to the explosion. All survived. Many were injured.some seriously. One of the Iraqis elaborated and with tears welling up said, "They'd run like any normal man would to save his life." "What he didn't know until then," he said, "and what he learned that very instant, was that Marines are not normal." Choking past the emotion he said, "Sir, in the name of God no sane man would have stood there and done what they did." "No sane man."
"They saved us all."
What we didn't know at the time, and only learned a couple of days later after I wrote a summary and submitted both Yale and Haerter for posthumous Navy Crosses, was that one of our security cameras, damaged initially in the blast, recorded some of the suicide attack. It happened exactly as the Iraqis had described it. It took exactly six seconds from when the truck entered the alley until it detonated.
You can watch the last six seconds of their young lives. Putting myself in their heads I supposed it took about a second for the two Marines to separately come to the same conclusion about what was going on once the truck came into their view at the far end of the alley. Exactly no time to talk it over, or call the sergeant to ask what they should do. Only enough time to take half an instant and think about what the sergeant told them to do only a few minutes before: ".let no unauthorized personnel or vehicles pass." The two Marines had about five seconds left to live.
It took maybe another two seconds for them to present their weapons, take aim, and open up. By this time the truck was half-way through the barriers and gaining speed the whole time. Here, the recording shows a number of Iraqi police, some of whom had fired their AKs, now scattering like the normal and rational men they were-some running right past the Marines.
They had three seconds left to live.
For about two seconds more, the recording shows the Marines' weapons firing non-stop.the truck's windshield exploding into shards of glass as their rounds take it apart and tore in to the body of the SOB who is trying to get past them to kill their brothers-American and Iraqi-bedded down in the barracks totally unaware of the fact that their lives at that moment depended entirely on two Marines standing their ground. If they had been aware, they would have known they were safe.because two Marines stood between them and a crazed suicide bomber. The recording shows the truck careening to a stop immediately in front of the two Marines. In all of the instantaneous violence Yale and Haerter never hesitated. By all reports and by the recording, they never stepped back. They never even started to step aside. They never even shifted their weight. With their feet spread shoulder width apart, they leaned into the danger, firing as fast as they could work their weapons. They had only one second left to live.
The truck explodes. The camera goes blank. Two young men go to their God.
Six seconds. Not enough time to think about their families, their country, their flag, or about their lives or their deaths, but more than enough time for two very brave young men to do their duty.into eternity. That is the kind of people who are on watch all over the world tonight-for you.
We Marines believe that God gave America the greatest gift he could bestow to man while he lived on this earth-freedom. We also believe he gave us another gift nearly as precious-our soldiers, sailors, airmen, Coast Guardsmen, and Marines-to safeguard that gift and guarantee no force on this earth can every steal it away. It has been my distinct honor to have been with you here today. Rest assured our America, this experiment in democracy started over two centuries ago, will forever remain the "land of the free and home of the brave" so long as we never run out of tough young Americans who are willing to look beyond their own self-interest and comfortable lives, and go into the darkest and most dangerous places on earth to hunt down, and kill, those who would do us harm.
God Bless America, and..SEMPER FIDELIS!
Optimum 6.5 Grendel bullet weights - stanc - 08-19-2011
RangerRick Wrote:In CQB often you are clearing a building so you want to be able to shoot through a wall to get the guy. Also stair wells are a pain to clear. If you can shoot up through the step above you and hit the guy hanging over the rail hosing you down, that's a plus.Sounds logical. What I was trying to get across to Joe, in regard to sectional density, is that the mass and velocity of an 85-90gr 6.5 TSX might give barrier defeat performance just as good as, if not better than, that of the 70gr 5.56 TSX, despite the lower SD. However, that could only be determined by adequate testing.
Quote:More and more bad guys are showing up with body armor, too.Well, like I told Joe, the soft copper TSX isn't going to defeat hard armor, but TSXs of any weight and caliber will go through soft armor. So I don't see sectional density mattering there.
Quote:Two Marines got the Navy Cross for stopping a truck bomber in Iraq. The engagement lasted 6 seconds. They both died. Who knows, maybe better barrier penetration and post barrier effects could have stopped the truck sooner.Maybe. Maybe not. An inspiring story, though.
Did some more reading on TSX vs barriers, last night. Apparently, windshield glass can adversely affect the expansion of TSX bullets of the same caliber, but different weight and impact velocity.
Also, the idea of a 6.5 TSX load may not even be necessary, especially with the development of the "barrier blind" SOST bullets. Plus, nothing more seems to have been heard of the 5.56 "brown tip" TSX load in the last three years, which may indicate it's been dropped from use by SOCOM.
Optimum 6.5 Grendel bullet weights - Variable - 08-19-2011
stanc Wrote:Tony's proposed, intermediate-length cartridge would require a rifle receiver longer than that for 5.56mm.
Longer receiver = heavier, bigger.
Ahh, OK, I thought you were talking about the Grendel.