Should A New 5.56mm Load Be Developed for The M4 ?

Flesh Thorn · Post by **Flesh Thorn** » March 5th, 2003, 3:47 pm

First of all, I have never got to shoot a M4. Shouldn't be a big deal. I've heard a lot of bitching about the M4 at ranges over a couple hunderd yards. The SOPMOD kit is great, but hits aren't doing the job that they should be. The M855/SS109 was designed for the A2,the XM193 for the A1 and maybe the M4,with its shorter barrel, needs a load tailored just for it.A 55 gr round, similar to the XM193, may produce better terminal ballistics than the current M855 62 gr. cartridge. Face it. We are not going back to a 7.62x51 cartridge.At least not in any great numbers. A totaly new cartridge could take a decade or more to develop so, a more effective 5.56mm round/load may be the answer.

Rgr_MindRiot · Post by **Rgr_MindRiot** » March 7th, 2003, 7:30 am

Hard to tell Slug. There always seems to be problems with new weapons when they first come out. I too have never seen an M4 but from your description of it i am inclined to believe that its barrel length is somewhat shorter than an A1/A2, more like a CAR15. While there are many factors that affect accuracy, the barrel length can also produce problems due to "sight radius". The same is true of handguns. A revlover with a 2" barrel is inherantly just as accurate with the same ammunition as a revolver with a 8" barrel. The difference is in the sensitivity of the shorter barrels sight radius. The shorter the radius the more sensitive it is to misalignment of the sight picture, the longer the radius the more forgiving it is. This is, of course, assuming that iron sights are being used at the range with the M4. The tell tale test of a weapons accuracty with any given ammunition is to bench rest the weapon so that it cannot move and fire it to see how the pattern prints. If you cannot establish a tight pattern in the bench rest then its time to investigate other possible causes ie. ammo, rifling, bolt, chamber, head space.....

Spartan · Post by **Spartan** » March 7th, 2003, 11:25 am

While I am not a ballistics expert, I have heard that a longer barrel increases round velocity as it will allow the propellent to burn more completely. A short barrel will complicate this. I have also heard, from a CSM of the Regiment, that a heavier projectile is what is needed for 5.56 to make it more effective, to slow it down and cause it to tumble more.

Flesh Thorn · Post by **Flesh Thorn** » March 7th, 2003, 1:06 pm

I'm no expert , but with a heavier projectile you need either a longer barrel or a tighter twist.The "tumble" is a result of the projectile yawing.In normal flight the axis of the projectile and the direction of travel are the same.When it yaws the axis is askew of the direction of travel resulting in a larger wound cavity.With a high velocity round like the 5.56 the stresses on the projectile often causes it to rip apart.The Russian 5.45x39 has a longer projectile with a hollow space near the head.This causes the round to yaw more and sooner upon impact.If it wasn't for international agreement we could use SP or HP ammo.The M855/SS109 was developed with the pentration of modern ballistic body armor in mind when fired from the M16A2.When fired from a M4, with a barrel lenght of 14.5 inches, the 62 grain round is even more ineffective.Also, an underfed and unarmored Afghan or Somalian is completely penetrated before the round has a chance to "tumble".

MrWesson22 · Post by **MrWesson22** » March 9th, 2003, 12:10 am

If designing a new cartridge altogether, why wouldn't you go up to something like a 6mm (.243)? Velocity with the shorter barrel is not going to be very high anyway. There's only so much powder you can burn in a certain length barrel. I could be completely off base here, but my thinking is if you're limited in velocity, you might as well make up for it in bullet weight.

freddytunafish · Post by **freddytunafish** » March 9th, 2003, 10:18 pm

There are various cardtriges in the .223/.243 range that are much more effective than our standard 5.56 but I dont know how easy it would be to convert our weapons to accept a different caliber bullet. I also dont know how well they would work in a combat scenario since they were made for hunting and what not. Then there is always the money issue. These specialty rounds dont currenly come in bulk and are much more expensive.

This round is .224 and quite a bit more effective. 55 grain bullet also.
.224 weatherby mag

Standard .223 for comparison.
.223

freddytunafish · Post by **freddytunafish** » March 9th, 2003, 10:29 pm

And couldn't we eliminate the problem of our rounds slicing right through and not causind much damage like how it was described in black hawk down by just using hollow point rounds. I know it is prohibited by the war crime laws but dont the SAS carry white phosphorous grenades which are also not allowed.

Rgr_MindRiot · Post by **Rgr_MindRiot** » March 10th, 2003, 7:36 am

While i would never consider myself a "techie" when it comes to ballistics, i would just like to say that long barrels do allow pressure to reach full potential inside the barrel thus allowing better accuracy at, and here is the point, longer ranges. So if you want to kill people, with a rifle, at long ranges ie. +300 yds, then barrel length etc.. will be one of several factors you should consider when selecting your weapon. However, for most soldiers including those engaging in urban combat, the ability to get rounds on target at longer ranges in a non-issue. For example, the average soldier is not capable of hitting targets at longer ranges even with a weapon capable of doing so, they just do not get the training and rarely can they see the enemy at that distance. Even if they can see the enemy it takes long hours of practice under simulated conditions to get rounds on a target at those ranges. As for the issue of "tumbling", tumbling is good :D You are having a really bad day when you encounter a tumbling projectile :( The bad thing about tumbling projectiles (we have already addressed the accuracy issue) is that they are great against soft tissue, doing alot of damage without overpenetration. Of course, this is also a weakness as they are easily deflected by even the smallest objects. Also, once the round begins to tumble is bleeds off energy fast or disentrigrates in the air. My opinion of the 5.56 round is that is a great fight stopper at close ranges and against soft targets, you can carry more ammo, it is easier to shoot for most soldiers due to low recoil, its cheap to manufacture, and if your ranger buddy is in the next room there is less of a chance that you will light him up through the walls as the round will fragment...not so with a 7.62 it will keep cooking right on through. So don't be discouraged by the performance of 5.56 at long range, it is a formidable round and has its distinct advantages over 7.62 when there is an open shot on the target.

dhutch07 · Post by **dhutch07** » March 24th, 2003, 12:51 am

Hello Rangers! I just want to say that this is the best site/forum ive seen to date. With that being said... Does anyone think that the REMFs that make up those UN rules would get their panties in a bunch if we went to a non crew served that put out 7.62? They would raise the LOAC flag before we could even test fire the bitch. My .02 Thanks... Hutch,out.

Spartan · Post by **Spartan** » March 24th, 2003, 11:10 am

Actually, there are quite a few 7.62 rifles in use by sniper teams that are not crew served. As far as assault rifles, it would take an act of congress to change everyone over to a new caliber, which is not unheard of. Congress would need to get involved mainly due to the conversion costs.

Even though the 5.56 does not kill on the first round as frequently as the 7.62, the thinking at the time 5.56 was introduced was that it was equally effective to cause serious injury to someone to disable several enemy that would be required to care for and remove an injured enemy from the field of battle, as compared to killing an enemy soldier outright.

Where the logic, if it was part of the decision to go to 5.56, falls down is where we fight an enemy in an urban engagement and they don't really have to go too far to evacuate an injured soldier to safety. This logic held true for one instance in time, the Vietnam war. It holds more water where there are logistical challenges for an opponent, such as the jungles of Vietnam or the deserts of Iraq where a soldier has to be removed far from the battlefield to access competent medical care.

But change the battle setting to an urban environment and adequate care can many times be provided just a few blocks away and other fighters can take the injured party's place immediately due to the concentration of enemy in the urban setting. In these cases 5.56 may not be too attractive and the need to drop an opponent with a single round is certainly more important than causing the serious injury of a poorly placed 5.56 round.

MrWesson22 · Post by **MrWesson22** » March 24th, 2003, 9:20 pm

I know AR15 uppers are presently available in 7.62x39 in several configurations. Of course the magazines are different, but I would think the conversion would not be nearly as expensive as adopting a whole new weapon since present weapons could be converted (keep the lower, change the upper). Of course, 7.62x39 isn't the most effective .30cal out there, but I personally would rather have a slower moving 180gr slug at my disposal than a fast moving 55 grainer especially in an urban environment when shots are probably to be fast and at close range.

Rgr_MindRiot · Post by **Rgr_MindRiot** » March 25th, 2003, 8:17 am

It's good to see some debate on what the "best" calibur cartirdge would be for our troops. From some of your post its is apparant that many of you believe that the 5.56 is an inferior round but, what i am really hearing is more about "personal preference" rather than actual facts. And, thats ok. When you are carring a weapon that fires a cartridge that you feel confindent about (all other characteristics about the weapon constant) then the psychological benefits are a positive thing. But the bottom line in stopping power as it applies to "one shot" stops is not the calibur of the ammunition rather it is the placement of the shot. I don't want to get sidelined on precision shooting in this post so let's look at what would constitute a "one shot stop", that is after being hit with one round the enemy cannot continue to fight. I know i will be going out on a limb with some of you with this next statement but, oh well i can take it. Here we go, "Most people do not die when they get shot". We have all grown up watching too many television programs where the good guys are shooting it out with the bad guys and after one guy gets shot with a single bullet, ususally a handgun round, he drops to the ground dead as Elvis, nothing could be farther from the truth. If some of you know a person who has been shot ask them about their experience (respectfully) or about those whom they have seen shot. They will tell you that while it might have stopped the fight from their perspective, it did not kill them and if they had to they could have returned fire even after being shot. Many people have been shot with various calibur weapons and have not only not died but could continue to fight even if they could not continue to advance against the enemy. So, what do you do now. You have shot the enemy with your super heavy duty weapon firing the most bad assed round and he is not only not dead but is still able to return fire on you. There are two ways out of this scenario so listen up, it may save you life or the life of someone you care about some day. The first way to stop the fight immediately with one shot is to execute what is called a "circuitry shot", with a round, preferably high velocity (any calibur will do). In English that means that your round penetrates his coconut or his spinal column (above the shoulder) in such a way as to drop him in him down in the top of his boots and he remains there motionless and uable to fight, in another word DEAD. That is a one shot kill and it does not happen very often. Oh what about a shot through the heart you say, well that is a kill shot but not necessarily a stopping shot, people have continued to fight for another thirty seconds after taking a roung through the heart. Well, what about multiple shots through the torso or extremeties you ask, again if you dont shut him down with a circuitry shot he can contiue the fight no matter what the damage if he is motivated enough - can you say fanatical muslim ?

So, whats the answer? Which is the best round to have, 5.56 or 7.62? It's simple so put on your thinking caps, here we go (point two). The "best" round is the one you can get multiple hits on target the fastest. This is especially true in the urban environment where multiple targets may present themselves at close ranges. A friend of mine was so pround of his .44 mag with all of its power that it just broke his heart when i told him i could put two in his chest, reload, and give him two more before he could fire his second shot. The lesson is he who shoots fast, shoots straigt, and gets multiple hits on target is rewarded with many unhappy enemies. Moral of the story, a big slow noise never killed anyone so, shoot fast (and accurately) and continue to shoot the target until it is no longer a threat ie Vulcan Dead. If he is moving, shoot him. If he is looking at you, shoot him. If he is flipping you the finger, shoot him twice more. We can discuss the the characteristics of various caliburs all day and still not reach consensus, there is so much misinformation out there. So, those of you who are going into to combat or if threatened with deadly force back in the world, shoot with the biggest calibur gun that you can get multiple hits on target quickly and continue to engage the enemy until you are sure he is no longer a threat. If you want more about "one shot stops" go talk to someone in a Sniper Unit.

Satis Verborem

MrWesson22 · Post by **MrWesson22** » March 25th, 2003, 9:40 am

Excellent post, Ranger Mindriot! The one shot stop statistics (which mainly focus on handgun caliber/load) that are out there can be quite misleading. 9 times out of 10, the one shot stop was a result of the assailant giving up and not as a result of his inability to fight. These of course pertain to self-defense shootings and not wartime situations. Shot placement will always be the key. Naturally getting multiple, well-placed shots center mass on your target is the most effective way to go (besides a head shot, which I imagine would be next to impossible to reliably do in a high intensity, fast moving combat situation). I'd still feel much more confident with 2 well placed rounds from a .308 than I would from a .22LR. Of course those are extreme examples, but I think the general idea is there. Shot placement and the number of fast follow up shots is the key, but the effectiveness of the round also plays a significant role in the equation. I'm by no means an expert, but I have shot 5.56, 7.62x39, and .308win (as well as numerous other calibers). .308 is a big step up in recoil from the other two, but 7.62x39 didn't feel much heavier than 5.56 to me. I'm talking about follow up shot speed here, in case that isn't clear. I know I would personally feel more confident with a rifle chambered in 7.62x39 than I would in one chambered in 5.56 NATO. If I were to design a battle rifle, neither of these calibers would be my choice. I just used them for the sake of comparison because most military types are quite familiar with both. I hope my unorganized thoughts here make sense.