Radio talk show host and TV commentator Hugh Hewitt is among a growing number of conservatives calling for monitoring the stockpiling of large-capacity ammunition feeding devices similar to how Sudafed is controlled.
Hewitt calls for photo IDs and records of purchases on firearm ammunition following the Oct. 1 shootings in Las Vegas that left 58 dead and 489 people wounded.
“If people buy a lot of ammunition in a short period of time, this should trigger a red flag with law enforcement,” said Hewitt on the NBC “Meet the Press” show on Oct. 8.
Monitoring ammunition stockpiling would be a way to let stockpilers know that law enforcement is keeping an eye on them. However, no guns or ammunition would be confiscated.
Officers who entered the room of the 32nd hotel floor used by the shooter were shocked to see the amount of weapons and ammunition the shooter had stockpiled. His victims were those who gathered nearby at the Harvest Country Music Festival.
Sudafed is regulated because pseudoephedrine, the active ingredient in some forms of medication, can be used to create the street drug methamphetamine, or crystal meth.
The federal act sets daily and monthly limits on how much of the active drug a person can buy.
When it comes to firearms and ammunition, there is no federal limit to how much a person like the Las Vegas shooter can buy, nor is there a national database of purchases.
A 1994 federal law, which expired a decade later in 2004, defined a large-capacity ammunition feeding device as a magazine, belt, drum, feed strip or similar device that has a capacity of more than 10 rounds of ammunition.
“Gun control won’t work but ammo monitoring could,” says John Carnes, conservative author and firearms expert.
Twice you read it in the commentary above. “Conservative” host Hugh Hewitt. “Conservative author and firearms expert” John Carnes. Actually, he somewhat misrepresents the gist of John’s article, who says this.
People should oppose gun control restrictions and registration requirements, but we shouldn’t let these turn our eyes from the existential threat of ammunition control. If ammunition printing ever becomes as cheap and effective as printing firearms parts currently is, then we can all rest assured that the right to keep and bear arms will never again be as infringed as it is today. Until that day comes, ammunition controls may be the most effective form of gun control.
He didn’t misrepresent Hewitt, apparently. I never really thought Hugh Hewitt was a conservative. But it does go to show that even the supposed conservatives are giving you up (case in point, the NRA, whose willingness to compromise empowered the controllers, who saw nothing but weakness). They don’t care about your rights, whether firearms or the ammunition to use in them.
I know, I know. The Supreme Court may block such rules and regulations, but they may not. They didn’t block the assault weapons ban, and Heller was a weak enough decision that it may even be used to bolster the ammunition control case.
I think a lot of people sense that the one weakness our community has is ammunition. This isn’t any different than it’s always been. Consider this report, the only significant piece of information in an otherwise stupid article.
“Everybody I know is stockpiling ammo,” said Allen, who came from Sacramento, as he carried a plastic bag bulging with bullets and gun parts. He declined to give his last name.
Sure, fight this in the political arena, fight this in the courts, and fight it in the town square and court of public opinion. But never assume you’re going to win. If at first we lose, the winning will come later.
There are approximately 300 million guns presently in the United States — probably much more if you count the illegal weapons. Even if the most stringent laws regarding gun control were passed, we would never see our country unarmed.
There is a simple solution that is largely ignored: Guns do not kill people — bullets do. Bullets are not good forever — guns are. The average life of a cartridge is 10 years; after that the primer is no longer dependable. Why can’t we limit the ownership of ammunition to a reasonable amount and strictly regulate the sale of bullets? Since the right to bear arms in the Constitution doesn’t state “and ammunition,” it would probably also hold up to challenge by the NRA.
Right now we strictly regulate the sale of narcotics and give hypodermic needles away to addicts. Hypodermic needles are the guns and narcotics are the bullets.
How do you like being compared to a drug addict? Still, there is wisdom is listening very carefully to your enemies. I think Sun Tzu said something along those lines.
As gun control goes, if the collectivists want to get the biggest bang for their buck, ammunition is the way to do it. Plan and act accordingly.
You’ll notice that I didn’t provide any expansion data. That’s because NONE of the .380 or .38 special rounds expanded at all! All of the bullets except for the two 9mm rounds could have been reloaded and fired. They had no expansion whatsoever.
They made that statement after testing .38 Spl, .380 ACP and 9mm in gelatin covered with several layers of denim. But here’s the problem to me. This data doesn’t comport with what Lucky Gunner found at all. It’s not even close.
If you take a look at Lucky Gunner’s testing protocol and test results, which were performed under tight control and strict boundary conditions, it’s clear that there is indeed expansion of most PD rounds regardless of barrel length. Mind you, some do better than others, and it’s also clear that the higher velocity imparted with longer barrels helps. But I just don’t see anything in the testing done by Active Response Training that even comes close to what Lucky Gunner found.
But regarding Lucky Gunner’s test results, I will offer up a few comments. First of all, the venerable .45 ACP, which I shoot, does well just about regardless of barrel length or ammunition type. Second, there are some good performers and some weak performers for every caliber. But on the average, the high performers seem to be Speer Gold Dot, Winchester PD rounds and Federal PD rounds (such as Hydra Shok).
Finally, I don’t really think anyone who ever gets shot with a .38 Spl round is prepared to call the gun that shoots it a “mouse gun,” even if it has a 2″ barrel.
Glenn Reynolds links TTAG where the author is discussing daily carry of reloads. It’s not a trivial discussion by any means, but something else caught my eye. See these comments.
If you have to use the pistol to defend yourself, which I presume is the reason you’re carrying it, you could be placing yourself in a very ill advised position by using reloaded ammunition, particularly in light of the prevailing legal climate. There’s nothing in that equation that bodes well for you.
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I agree with Mr. Savage. My reloads are better than a lot of factory cartridges for the same reason your mom’s apple pie beats anything you can buy at the grocery store.
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Just beware that in the aftermath of a defensive shoot, you will get destroyed in court for using reloads. Even if you did everything else right, even if you prove the shoot was self defense, the few dollars you saved could cost you everything you own. A halfway decent prosecutor can convince a jury that you created a round that causesd undue suffering, that only a madman predispoaed to violence would.use. Legally, the best defensive ammo is what the police use, for it destroys any argument a prosecutor may present that the ammo was used for some nefarious purpose. I know, it is silly, but that is what happens in our courts.
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Regarding the use of reloaded ammo causing extra jeopardy in court, please cite a case where this happened. Otherwise, I call BS.
For years, I’ve warned people that there are a couple of serious concerns with using handloaded ammunition for personal or home defense. The big one is forensic replicability when the shooter is accused, and opposing theories of distance become a factor.
How often does this happen? One time some years ago, that question came up on an internet debate. I looked through the ten cases I had pending at the time as an expert witness, and gunshot residue (GSR) testing to determine distance from gun muzzle to the person shot was an issue in four of them. Forty percent is not what I’d call statistically insignificant.
[ … ]
… if you have any friends who use handloads for serious social purposes, please share. You might just save them from the sort of nightmare suffered by the defendant in New Jersey v. Daniel Bias, who was bankrupted by legal fees before the first of his three trials was over, and wound up serving hard time. Both of his attorneys were convinced he was innocent, and told me they believed that if he had simply had factory ammo in his home defense gun, the case would probably never have even gone to trial.
So there you have it. The commenters are advised to get around a little more.
While not a panacea, reloading can give you a temporary hedge on politically driven market shortages by allowing you to build up an adequate store of ammunition while the components are readily available and still reasonably priced. Second Point: On a more personal level, I absolutely love the fact that reloading gives me the ability to custom tailor ammunition for each of my firearms, thereby maximizing the performance and versatility of every firearm in my collection.
I’ve never been a reloader, but there are advantages to it if you know how, including a level of QA likely not brought to the task by factory loads. Then again, Massad Ayoob has a warning for you concerning handgun ammunition.
For years, I’ve warned people that there are a couple of serious concerns with using handloaded ammunition for personal or home defense. The big one is forensic replicability when the shooter is accused, and opposing theories of distance become a factor.
How often does this happen? One time some years ago, that question came up on an internet debate. I looked through the ten cases I had pending at the time as an expert witness, and gunshot residue (GSR) testing to determine distance from gun muzzle to the person shot was an issue in four of them. Forty percent is not what I’d call statistically insignificant.
[ … ]
… if you have any friends who use handloads for serious social purposes, please share. You might just save them from the sort of nightmare suffered by the defendant in New Jersey v. Daniel Bias, who was bankrupted by legal fees before the first of his three trials was over, and wound up serving hard time. Both of his attorneys were convinced he was innocent, and told me they believed that if he had simply had factory ammo in his home defense gun, the case would probably never have even gone to trial.
Remember that if you ever have to shoot in self defense, the entirety of the legal system – witnesses, judges, juries, police and prosecutors – is stacked squarely against you. Do you need anything else in that stack?
There are a lot of articles and discussion forum threads on barrel twist rate for AR-15s. So why am I writing one? Well, some of the information on the web is very wrong. Additionally, this closes out comment threads we’ve had here touching on this topic, EMail exchanges I’ve had with readers, and personal conversations I’ve had with shooters and friends about this subject. It’s natural to put this down in case anyone else can benefit from the information. Or you may not benefit at all. That’s up to you.
This is a discussion about 5.56mm ammunition and barrel twist rates (and later, about the shooter and ammunition quality). If you wish to debate the effectiveness of the 5.56mm round generally, or wish to disparage the choice of the Eugene Stoner system, I’m sure there are forums for you. This is not it.
In the real world, ammunition isn’t concentric, and even if it is almost precisely concentric, pour density can be slightly different throughout the ball, and voids can develop. This causes gyroscopic stability problems with bullets, even in the best manufactured ammunition. But much ammunition would not be considered the “best manufactured ammunition.” Ammunition will only be as good as the QA under which it was made.
When center of gravity is off-axis it can cause bullet lateral throwoff, yaw and a host of other problems with bullet trajectory. In order to overcome these problems, rifling twist achieves this gyroscopic stability for the bullet, thus negating the effects of the manufacturing process (at least in part).
Conventional wisdom taught us that slower twist rates wouldn’t properly-stabilize a bullet, causing it to yaw. On the other hand, faster rates could over-stabilize lighter bullets, causing similar problems. This is correct in theory—however, modern ballisticians have pretty much de-bunked the over-stabilization theory as a practical matter. All things being equal, it is better to have too much twist than not enough.
While his statement is a bit imprecise, there is something very precise about it. It is precisely wrong. Yet there are much cleaner and simpler explanations of why high twist rate is not always good. One commenter at this discussion thread summed it up well.
You can certainly overstablilze (sic) a bullet if you spin it so fast it doesn’t nose over at the top of its trajectory … Best thing to do is not spin bullets any faster than what’s needed for best accuracy.
Correct. If a bullet is overstabilized, it tends to stay pointed along its axis of rotation, even on the final (downward) part of its trajectory. This can cause keyholing, odd aerodynamic effects (flying sideways through the air) and even bullets to wildly spin off trajectory.
Bullets from rifled barrels eventually achieve stability by yawing back and forth, while undergoing a larger revolution about the major axis of the trajectory. So quite obviously, it’s necessary to spin the bullet, and to spin it enough to give it stability, while protecting the need to nose over on the final part of its trajectory. Getting this twist rate and spin right has been a matter of much testing, internet fights, and lot of engineering study and heavy spending by the taxpayers. I know that my guns perform well, and so I decided to contact my manufacturer for his opinion on the matter.
In the interest of full disclosure, I have two Rock River Arms rifles, one Elite CAR A4 with a 16″ Barrel, twist 1:9, Quad Rail, and another competition gun with a muzzle brake and 18″ SS barrel with a twist rate = 1:8. I have recommended RRA rifles to my readers before, but there are many good guns on the market. Your probably have one. I sent a list of three questions to RRA, and Steve gave me these responses (the question isn’t included because it wasn’t forwarded back to me, but it’s apparent what I asked except for the first question, which was basically does RRA warranty their 1 MOA for both M193 and M855. This is Steve’s response.
Herschel,
Thanks for your questions. I’m going to take them in reverse order.
3. 1:9 is adequate for many, but not all rounds typically used in an AR platform. Between .223 Remington and 5.56mm NATO, there are rounds from 45 to 90 grains (that I am familiar with) and I know of, but have never shot, lighter and heavier rounds. No single twist is going to handle all of them. 1:9 is adequate for a sizable number of them, however…including the two most commonly available, in bulk and at reasonable prices…55gr FMJ (M193)and 62/63gr FMJ (M855). It is not ideal for rounds lighter than 50gr nor those over 68 or 69 grains, which is why there are other twist rates commonly available…including from RRA. We offer a 1:12 24” bull barrel for our Varmint hunters who prefer to use the lighter bullets for prairie dogs and other targets, and both 1:7 and 1:8 barrels in a variety of configurations for those who want to shoot heavier bullets…up to and including the newer 77gr loads and 80gr VLDs. We’ve also run custom twists for a limited number of contracted purchases.
2. Yes. 1:9 does well with both M193 and M855. Different barrels perform differently, but 1:9 generally stabilizes both weight/length bullets fairly well, It neither over nor under spins either and does not produce key holing.
1. The hardest question to answer. Neither M193 nor M855 are notoriously accurate rounds. They meet military, not match, requirements. Our accuracy claims are the rifle’s capability…but the shooter and ammo have to do their parts. There are loads that are commercially available and claimed to be “M193” and “M855” equivalents that clearly aren’t, and they aren’t capable of ”minute of bad guy” at 100 yards, let alone the .75 to 1.5 MOA claims that we make for our different rifles. That is no reflection on our rifles or barrels, or the shooters…unfortunately there is some real crappy ammo on the market today, which will not perform well out of any barrel, of any twist rate.
Thanks.
Steve/RRA
This is a good response, but let’s not stop here. While perhaps not recalled by some, American Rifleman has given us a fairly comprehensive look at 5.56mm ammunition and barrel twist rates in an article entitled Testing The Army’s M855A1 Standard Ball Cartridge. It is rich with history on how the Army fielded the M855A1. Ignore the issue of the M855 versus the M855A1 for a moment and consider the background.
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.
Don’t slip past these paragraphs, because they explain why “Milspec” is 1:7. It isn’t because 1:7 shoots M193 or M855 more accurately. It’s because of the weight of tracer rounds. As we’ve discussed before, the term Milspec doesn’t mean better, or worse, or anything at all except that it precisely meets the specifications outlined in the purchase order(s), excepting whatever variance notifications they might make on a given batch of guns.
The M855A1’s developers have described it as yielding “match-like” accuracy, which most rifle shooters would define as one minute-of-angle (m.o.a.), or groups measuring no more than 1 inch at 100 yards. While the new ammunition has proved more accurate than the green-tipped load it replaced, testing did not yield match-like accuracy, especially in the standard 1:7-inch twist-rate found in today’s M4s and M16s. At 100 yards, the best group with a 1:7-inch barrel was 1.62 inches (1.6 m.o.a.). At 300 yards. it similarly fired 1.6 m.o.a. (4.9 inches) and widened to 1.8 m.o.a. (7.5 inches) at 400 yards. At these same distances, firing the M855A1 through a 1:9-inch twist barrel reduced group sizes by approximately half.
The tests demonstrated that 1:9 twist produced better accuracy, approximately twice as accurate. Now take note what the testers found with the newer M855A1 regarding repeatability.
On average, the new ammunition produced one flyer in roughly each five rounds, which, it can be argued, exaggerated the group sizes. Since the Army announced that, “On average, 95 percent of the [M855A1] rounds will hit an 8×8-inch target at 600 meters,” each group’s most errant bullet impact was discarded and group sizes recalculated. Statistically they improved, but not enough to place 95 percent of rounds so close at 600 meters, at least when using the standard 1:7-inch barrel-which may explain why accuracy was less than expected.
There is one “flyer” in every five rounds. This seems to me to be a significant problem with this ammunition combined with the barrel twist, and the commenters don’t seem to like it very much either. Finally, this.
When U.S. Army shooters twice fired public demonstrations of the new round, they did not employ standard 1:7-inch twist M16A2s or M4s, but accurized, match-grade, stainless-barreled rifles from the Army Marksmanship Unit (AMU). I contacted the AMU and learned that these rifles did not have standard-issue 1:7-inch barrels, but most likely 1:8-inch twist, which probably accounts for their “match-like” accuracy.
Isn’t that rich? The Army made claims of “match-like accuracy,” and proved the rounds shooting out of different barrels than are deployed with Soldiers, using 1:8 twist, not 1:7 twist.
The American Rifleman article goes on to discuss in some detail the performance of the M855A1 with slim-profiled targets like malnourished tribal fighters in Afghanistan (so-called “ice picking” the target without fragmentation), performance at barrier penetration (concluding that it is better than its predecessor), and its lethality once it does penetrate barriers. I recommend this reading to you. It’s well worth the time.
So to summarize what we know, remember some basic things. First, the bullet has to be spun to give it gyroscopic stability. This spin needs to match the bullet (including mass and length), and care must be taken not to over-stabilize the bullet. If you shoot typical .223 ammunition (55 gr.), or M193 or M855, a twist rate of 1:9 is probably just about ideal. You’ll probably lose some accuracy with a higher twist rate.
This loss of accuracy is likely not significant for a lot of shooters. If you shoot much heavier ammunition (and there is a lot on the market), you probably need to consider a twist rate of 1:8. Finally, none of this matches the value of good ammunition or good shooting.
That’s the good news. Most guns can outperform the shooter, and I know that’s the case with me. I’m a decent shooter. Not great, but decent. I’ve taken my Tikka T3 .270 bolt action rifle and literally put rounds through the same hole at 100 yards (with slightly more tearing of the same hole in the paper). On the other hand, this is with a good scope, no wind, a cool and comfortable day, all day to work my craft and thus no time pressure, no one else to be concerned about, lots of coffee to wake up, and a full belly.
But if I had kept records, it wouldn’t have happened again exactly like that since, theoretically, even with perfect ammunition, considering barrel harmonics and that physical processes like this are a heuristic phenomenon, if I had continued to log my shots this way, it would have doubtless shown a standard distribution (distance between each shot and mean).
But regardless of the details, you’ve done it before. Control breathing … get good sight picture … back out of the shot if you’re not mentally right … know where your trigger breaks … and so on. You know the drill, since you’ve done it many times. It’s perhaps the purest pleasure a shooter can have.
Now throw in simple annoyances like a whining partner at the range, losing daylight and time pressures, hunger, and any of the other 100 possible nuisances that can sap your accuracy. Then your accuracy goes to hell, doesn’t it? Now, combine that with wearing heavy gear and being shot at, and I’m sure it diminishes your control over your weapon. Thankfully, I only have the experiences of my former Marine son conveyed to me.
The good part of this is that regardless of your barrel twist rate, if your AR-15 is reliable, even if it’s not top of the line, it can probably outperform you. That means getting better isn’t a matter of getting a new rifle or barrel with a different twist. It means practicing with your rifle, sometimes under duress. It also means buying good ammunition. Steve at RRA is right. The shooter and ammo have to do their part. I object to cheap ammunition just like I object to cheap engine oil. I’m trying to develop the discipline at the store or online to buy better ammunition.
Right, I’ve got it. I feel your objection. Good ammunition (e.g., Hornady $2 per round .270 for my Tikka) hurts. This is my wealth, and it’s hard to part ways with it since it’s hard to earn it. But using bad ammunition at the range makes it hard to impossible to assess your practice. Use of my value pack Federal .223 at the range means that my accuracy is irrelevant if I’m using the same reticle holdovers I would for 5.56mm since the muzzle velocity is different (and very slightly lower than the 5.56mm). You’ve got the picture.
The best way to get better accuracy is probably not to get a better gun. It’s to practice with the one you’ve got.
Here is a related video I found interesting on gyroscopic stability. He’s wrong about the math being incomprehensible, but it is rather difficult if you’re involved with partial differentials or worse, the Navier-Stokes equations in CFD. You need some specialized training in mathematics in order to tackle that. You don’t have to know any of that in order to understand the basics of shooting.
This discussion probably won’t end the debate on barrel twist rate, and it certainly won’t end the fight between the Army and Marine Corps (who doesn’t want to deploy the M855A1). But I hope it was helpful to you.
We have previously discussed the Marine Corps battle with the Army and Congress over fielding a different ammunition than the Army, who spent a wad of money on an “environmentally friendly” lead-free cartridge, the M855A1.
Currently, the Marine Corps is trending towards the MK 318, which appears to be a far superior round, and it comes in right at 2900 FPS out of the M4 barrel, higher for longer barrels. The claim is that it behaves better at longer distances and retains its ability to penetrate.
This trend towards heavier rounds has been going on for some time now, and 62 grains isn’t the top weight for the 5.56mm bullet. One reader sends information about Sierra 77 grain, and tells me that the 1:9 twist is just fine with this ammunition. Of course, one gives up something to get something. In the case of heavier bullets, you give up muzzle velocity.
This velocity detriment may seem small. TFB likes the Sierra 77 grain, and informs us that its muzzle velocity comes in somewhere between 2500 FPS and 2600 FPS. But your choice of ammunition will depend upon your target, its distance, any interstitial shielding, potential body armor, etc.
You may do better with M193 than with either the MK 318 or the Sierra 77 grain. Sometimes the smaller rounds with the higher muzzle velocity are what’s needed to penetrate any armor. Do you not believe me? Consider what we learned with the FN 5.7 and its test against bulletproof glass, which only the .454 Casull could penetrate. The open tip 5.7 round at 22 grains penetrated the glass due to high muzzle velocity, whereas the heavier 5.7 round did not.
Do you need more evidence? Very well. Consider that AR500.com sells hard plates it calls Level III, and those plates are rated to stop M855 (steel core) but cannot stop M193. They have to move up to what they call Level III+ to perform effectively against the M193 due to its higher muzzle velocity compared to the M855. There’s nothing wrong with having a safe full of M193.
The bill has already passed the House and is expected to be voted on and approved by the Senate this week before going to President Obama’s desk for his signature.
This is not the first time Congress has gotten its dander up over this subject. Lawmakers asked both services to explain the same thing last year, but Marine Corps leaders said they need to do more testing of the Army’s M855A1 enhanced 5.56mm round.
I reached out to the Marine Corps yesterday and the Army today to ask about how they planned to deal with the request. I could almost hear the head-scratching as if neither service had heard anything about it.
According to the provision, the report must be submitted within 180 days after the bill, which includes the entire defense budget for the coming year, is enacted.
If the secretary of defense does not determine that an “emergency” requires the Army and Marine Corps to use the two different types of rifle ammo, they must begin using a common 5.56mm round within a year after the bill is passed, it states.
OK so here is the back story for those you out there who don’t know it.
The Army replaced the Cold-War era M855 5.56mm round in 2010 with its new M855A1 enhanced performance round, the end result of more than a decade of work to develop a lead-free round.
The M855A1 features a steel penetrator on top of a solid copper slug, making it is more dependable than the current M855, Army officials have maintained. It delivers consistent performance at all distances and performed better than the current-issue 7.62mm round against hardened steel targets in testing, Army officials maintain. It penetrates 3/8s-inch-thick steel at ranges approaching 400 meters, tripling the performance of the M855.
The Marine Corps had planned to field an earlier version of the Army’s M855A1 until the program suffered a major setback in August 2009, when testing revealed that the bismuth-tin slug proved to be sensitive to heat which affected the trajectory or intended flight path.
The setback prompted Marine officials to stay with the current M855 round as well as start using the MK 318 Special Operations Science and Technology round developed by U.S. Special Operations Command instead. Commonly known as SOST ammo, the bullet isn’t environmentally friendly, but it offered the Corps a better bullet after the Army’s M855A1 round failed.
Since then the Marine Corps has purchased millions of MK 318 rounds.
The MK 318 bullet weighs 62 grains and has a lead core with a solid copper shank. It uses an open-tip match round design common with sniper ammunition. It stays on target through windshields and car doors better than conventional M855 ammo.
The Army quickly replaced the bismuth-tin slug in its new round with a copper one, solving the bullet’s problems in 2010, Army officials said.
The new Army round also weighs 62 grains and has a 19-grain steel penetrator tip, 9 grains heavier than the tip on old M855 ammo. Seated behind the penetrator is a solid copper slug. The M855A1 consistently penetrates battlefield barriers such as windshields more effectively than the M855, Army officials contend.
The accuracy of the MK 318 may not be what it’s cracked up to be. However, for any of these heavier than 55 grain rounds, there is a detriment in muzzle velocity (these rounds lose up to 200 FPS), and that can actually make a difference in penetrating capability.
Suffice it to say that creation of an environmentally friendly round for the armed forces is laughable, and the main thing to be concerned about is ballistics. It would be interesting if someone still in the service would weigh in on this debate.
But as for Congress being briefed on the details of the ammunition being chosen by the armed forces, I agree with one of the comments. You may as well try to teach physics to a pig.
Defense contractor Textron just unveiled a new rifle at the Modern Day Marine conference. Designed to use so-called “telescoped” ammunition, the new rifle promises a harder-hitting, lighter bullet for America’s ground troops to fire. Whether the U.S. military is ready to embrace all the change a new rifle and ammunition would bring remains to be seen.
Traditional bullet cartridges have a bullet seated roughly halfway inside a brass shell casing, with gunpowder inside the casing. By contrast, the new rifle uses a 6.5-millimeter polymer-cased telescoped bullet. Telescoped rounds feature a bullet completely encased in a polymer shell, like a shotgun, with gunpowder surrounding the bullet in the shell.
The result is a cartridge that doesn’t use brass, a considerable savings in weight. According the Kit Up! blog, telescoped ammunition is about 40 percent lighter than traditional ammunition. Textron could have channeled this weight savings into making lighter ammunition, but instead it chose to make new ammunition that packs a bigger punch. The rifle—and 20 rounds of ammunition—weighs a total of 9.7 pounds. By contrast, the standard M4A1 (pictured above) and 30 rounds of ammunition weigh 8.74 pounds.
Textron claims the new 6.5-millimeter round has 300 percent more energy than the standard U.S. Army bullet, the M855A1. That translates into greater knockdown power against human targets, more armor penetration, and longer range. A heavier bullet and more energy would solve a persistent complaint about the U.S. Army’s M4A1 carbine—that the smaller 5.56-millimeter bullet often requires multiple hits to incapacitate a target and it lacks the range to make accurate long-range shots. The latter has been a particular complaint in Afghanistan, where long-range engagements are common.
Textron’s rifle is a gas-operated, piston-driven rifle that has many familiar features drawn from the M4A1, including a charging handle and gas block. It features military-standard rails for the attachment of devices such as flashlights and lasers, and what appears to be Advanced Armament Corporation flash hider. The front and rear sights, pistol grip, and buttstock are all from firearm accessory manufacturer Magpul.
Well, whatever. It isn’t clear why the round has more energy. That could be due to greater bullet mass or bullet velocity or a combination of both. The mass of the bullet, grains of powder, muzzle velocity and other information are left unsaid.
If it has a higher muzzle velocity, then that will come with side effects such as shooting the barrel rifling out sooner than with the M4. I could be wrong and commenters may correct me, but my understanding is that the guys who shoot .243 in competition have to be sponsored due to having to change barrels out so frequently (at 4000 FPS the barrels are good for only several hundred rounds and then they have to be replaced to maintain accuracy).
If the bullet has more mass along with more powder to propel it the same velocity as the 5.56 mm (~ 3150 FPS), then it has more recoil which will cause a change in the ability of the shooter to retain sight picture (a huge advantage of the low recoil 5.56 mm). You don’t get something for nothing.
The 5.56 mm round has ended the lives of many enemy fighters in Vietnam, Iraq and Afghanistan. It has a long history of being a highly proficient round, and most complaints about its effectiveness are due to the inability to properly utilize it.
I’ll stick with the Stoner design, thank you. If the new cartridge is worth anything, it’ll have to prove its mettle in battle.
The never-ending caliber debate can be tiresome, but then again occasionally there are good and useful additions to the body of knowledge. Because of my son being deployed, I have always known and understood (not first hand, but second hand) the utility and superior performance of the 5.56mm in the field (and when I say “field,” I mean Fallujah, not your local shooting range where your know-nothing, tacticool weekend warrior waxes stupid in front of everyone).
I have also heard from his teammates about being shot by the 7.62×39. Specifically, Corpsman Prince gave me details of his experience.
He was very kind and friendly, well trained, in excellent physical condition, and had absolute commitment to his fellow Marines. He showed me his wound from Iraq within several days of returning. A round from an AK-47 had entered through the front part of his lower thigh, ricocheted up his thigh, and exited out of the very upper part of the back of his thigh. Entry and exit wounds (now scars) were at least a foot apart.
Corpsman Prince stayed in Iraq and did his own rehabilitation during the deployment. The hardest thing about the experience, he told me, was getting enough pairs of clothing after each successive pair became blood stained. The more interesting thing about what happened that day with Corpsman Prince was what happened to his fellow Marines. He wasn’t the only one who was wounded in that engagement. Several other Marines were also wounded, and Prince had to treat them before he could treat himself. He did so while bleeding out.
The exit wound was small, virtually as small as the entry wound (if the scar is any indication of the wound size when it happened). The scars I saw were identical in size.
But the specific addition I wanted to mention has more authority than anything I can muster. It comes via Defense Review, from Tacmed Australia. I will quote at length, and then offer up a disagreement and an agreement.
Admittedly I’d rather not be shot with either, but if I had to choose, I’d take a round from the AK47 over the M4 any day of the week. To understand why, it’s important to have a very basic look at the physics behind terminal ballistics, in this case being the science of what happens when a penetrating missile enters a human body. The first place to start is the Kinetic Energy Equation:
KE = ½ M (V1-V2)2
Breaking this equation down into its components, we have Kinetic Energy (KE) influenced by the Mass (M) of the penetrating missile, as well as the Velocity (V) of the missile. This make sense, and it is logical that a heavier, faster missile is going to do more damage than a lighter, slower missile. What is important to understand is the relative influence that Mass and Velocity have on Kinetic Energy, as this is key to understanding why I’d rather be shot by an AK than an M4. You’ll notice that the Mass component of the KE equation is halved, whereas the Velocity component is squared. For this reason, it is the Velocity of the projectile that has far more bearing on the energy that it dissipates into the target than the mass. The V1-V2 component of the equation takes into consideration that the projectile might actually pass straight through the target, rather than coming to rest in the target. In this instance, the change in the Velocity of the projectile as it passes through the target (V1 being its velocity as it enters, and V2 being velocity on exit) is the factor that is considered when calculating how much energy the missile delivered into the target. Naturally if the projectile comes to rest in the target (ie: no exit wound) then V2 equals zero and the projectile’s velocity as it entered (V1) is used to calculate the KE.
That’s enough physics for now, but you get the concept that the optimum projectile to shoot someone with is one that has a decent mass, is very, very fast, and is guaranteed to come to rest in your target, as to dissipate as much energy as possible into them, and hence do maximal damage.
The next concept to grasp is that of permanent cavitation versus temporary cavitation. Permanent cavitation is the hole that gets left in a target from a projectile punching through it. You can think of it simply like a sharp stick being pushed through a target and leaving a hole the diameter of the stick. The permanent cavity left by a bullet is proportionate to the surface area of the bullet as it passes through the tissue. For instance, if a AK47 round of 7.62mm diameter at its widest point passes cleanly through a target, it will leave a round 7.62mm hole (permanent cavity). If this hole goes through a vital structure in the body then the wound can be fatal, however if the bullet passes through soft tissues only then the permanent cavity can be relatively benign. This is a slight oversimplification of the concept, as bullets will rarely remain dead straight as they pass through human bodies, as they have a tendency to destabalise, and for the heavier back end of the bullet to want to overtake the front. This concept, known as yaw, increases the frontal surface area of the bullet as it passes through tissue, and hence creates a larger permanent cavity.
Here is my disagreement so far. I’m not certain that the author understands the distinction between cavitation and creating a cavity (or perhaps it is that he isn’t clearly delineating the difference). Cavitation has to do with the formation of voids due to change of state of a liquid to a gas, whereas some of what he is discussing has to do with the yawing and fragmentation of the 5.56mm round in tissue. There are both of these effects at work.
We’ve discussed the rocking back and forth in flight that occurs with the 5.56mm round, based on the very well researched paper Small Caliber Lethality: 5.56 mm Performance In Close Quarters Battle. This rocking back and forth during flight, which occurs even with boat tail 5.56mm, causes rapid yawing when it enters tissue. Fragmentation ensues, ensuring multiple fragments take different trajectories through tissue. This may be what the author is referring to when he mentions permanent cavity. Or then again, he may be referring to the high velocity of the 5.56mm round, and as I said above, both effects are at work.
But by mentioning Newtonian physics, he is on to something. It’s not only the energy of the projectile that’s important, but the velocity term is a function of the exit velocity, which means that it’s also important how much energy gets deposited in the object. If the bullet doesn’t stop, fragment, or otherwise leave its energy in the object, it will not do as much damage as one which does. It’s the same way with, for example, radiation. A high energy gamma (e.g., from N-16) can pass through a piece of tissue without ever interacting with orbital electrons and ionizing atoms. Thus, high energy photons can pass through a body without causing dose, depending upon depth, energy, etc.
In order to demonstrate the point, he provides two videos, one of 5.56mm in ballistic gelatin, and one of 7.62 in ballistic gelatin. But the most impressive thing the author does is convey his own experience treating wounds from 7.62 mm and 5.56 mm rounds, and then show you what an X-ray looks like of an upper thigh and femur that has been hit with a 5.56 mm round from a couple of hundred meters.
As I said, this was from a couple of hundred meters. Ponder on that a bit. While this article doesn’t specifically address the .308/7.62×51, some of the principles are applicable.
7 years, 4 months ago
