.30 cal FMJ rounds, what makes them better then 5.56 FMJ?

[Vern Humphrey]

For combat, when you shoot at people, they tend to hide, get behind things and so on. You will often find yourself shooting at suspected locations, "working" them by shooting at and around them. You need PENETRATION. You need to be able to shoot through dirt parapets, logs, walls and so on. The very best penetrating round is the old .30 cal AP round, with the 7.62mm version right behind it.

 

[Jenrick]

The Big D: Temporary or stretch cavity, is really not an issue except in two cases. The first is if you hit an internal structure which is not made of highly elastic tissue (the liver or kidneys for example), the second is when the temporary cavity is of a size to be larger than limit of tissue elasticity of the area of the body hit. The second only really applies to limbs if you're shooting something smaller then a .50 BMG (even a .338 laupua doesn't generate nearly a large enough temporary cavity to cause an issue in the torso).

The Alaskan:

I suspect 30 cal shooters don't discuss "fragmentation, expansion, yaw" etc because it's not terribly relevant. You said you're looking at buying an M1A.

Fragmentation, expansion, and yaw are the three ways a bullet can increase the permanent wound cavity which is the only way to cause injury. A .30 cal shooter who doesn't discuss these isn't doing their homework.

The main reason fro the 30 cal popularity is straight out penetration. 30-06 ball ammo will blow through a lot more cover than those AR15 pop guns. (Comparatively speaking, of course.) Add to that, you get the ability to effectively hit target out past the AR15's maximum effective range of 550 meters. At least that's the number they made me memorize in the Army.) Trouble is, you pretty much never get an opportunity to use that long range in battle-historically speaking.

If it was just penetration, then why not issue AP rounds all the time? M995 (5.56 AP) will do a dandy job of punching holes through things .30 cal M80 ball might have issues with. I certainly agree that a .30-06 black tip AP round will certainly outperform M995 in penetration, but a .30 call pencil hole is nothing special ballistically (it's basically a narrower wound cavity then a .38 spl hard cast wadcutter). I'll give you the distance argument, but in WW2-Vietnam, the engagement range really never moved out into the distances where 500 meters was doable too often.

I know that if I hit someone with a 30 cal bullet, he's going down. You can talk about terminal ballistics all you want, and, most assuredly, those remarks have some validity, but the 30-06 ball bullet served this country well for half a century and through two world wars and a smaller war (Korea). There are literally MILLIONS of dead soldiers lying in battlefield graves all over the globe that will attest to the 30 cal's efficacy. It's kind of hard to argue with that kind of success-with or without a slide rule.

Okay this is exactly what I'm talking about. Yes I know the .30 cal M2 ball round has put a lot of people in the ground. So have a lot of other calibers. Why does the .30 cal round (in whatever flavor, .30-06, .308 etc.) have this reputation and following is my question? What makes it so dang effective? As I mentioned earlier in this post, there are three things a bullet can do to increase its permanent wound cavity. .30 cal M2 ball really doesn't do any of them, so WHY is it effective? Again, it really makes a wound track about equivalent of a .38 wad cutter, so why is one considered the hammer of righteousness and the other a really good way to get yourself killed in a gunfight?

Daisycutter:

Diameter is only one dimension. Multiply the difference by 3.14 or π to get a better perspective in terms of circumference... Or square the radius and then multiply by 3.14 for the area. The difference grows dramatically, and you're only still in the 2-dimensional world. You gotta multiply by the cube (^3) before you get a real appreciation why it would feel different in the real world.

See post #11 for the math already done in 2 dimensions, the overall volume of the round really doesn't matter as it's basically cutting a channel based on it's exterior dimensions. I will say that volume and mass do effect penetration depth.

The 30 caliber is substantially larger, generally carries about double the energy, and causes far greater damage based upon a long history of empirical data.

Not to mention one of Newton's Laws regarding an equal and opposite reaction. The recoil difference between a 30-06 and a 223 should be a clear indicator of each projectile's felt "effectivity" on the receiving end.

So the effectiveness of the round is based on KE then? Even if a through and through wound (a very common occurrence with M2 and M80 ball) doesn't really have much energy deposition?

I'm not arguing with anyone that the .30 bullet has a well proven track record of effectiveness. I just want to know WHY. If you test M2 or M80 ball, it's really nothing special in terms of terminal ballistics. Is its reputation just built on it's track record, from when nothing else was available or is there actually something to this round that's generally not noticed or discussed?

-Jenrick

 

[C-grunt]

Modern terminal ballistic research says that projectiles moving faster than 2000 FPS can produce temporary cavities large enough to cause damage outside of the wound channel caused by the bullets. M80 ball does indeed yaw, most base heavy spitzer bullets will.

 

[The Alaskan]

Jenrick: like I said earlier-you're over analyzing this. Stop looking at the math and look at the results.

"Fragmentation, expansion, and yaw are the three ways a bullet can increase the permanent wound cavity which is the only way to cause injury. A .30 cal shooter who doesn't discuss these isn't doing their homework."

Probably true. You keep doing your homework and get back to me on that. I don't need to know the math. I know the history.

"If it was just penetration, then why not issue AP rounds all the time?"

Good question, I suspect it might have something to do with a.) cost and b.) wear on the barrel. But that would be nothing more than an unsubstantiated guess on my part. (And I'm not fond of doing that.) However, US soldiers in the 2nd World War preferred the black tip AP round almost exclusively over the standard ball round and would use it exclusively whenever there was enough around.

"M995 (5.56 AP) will do a dandy job of punching holes through things .30 cal M80 ball might have issues with."

LOL! Seriously!? Like what? Name ONE thing a 223 round will penetrate that a 30-06 or 308 won't. Just ONE.

"Okay this is exactly what I'm talking about. Yes I know the .30 cal M2 ball round has put a lot of people in the ground. So have a lot of other calibers. Why does the .30 cal round (in whatever flavor, .30-06, .308 etc.) have this reputation and following is my question?"

Because it works. It just does. It has proven itself over and over and over and over again, for generations of soldiers to the point that the efficacy of 30 cal firepower is now beyond repute. I apologize if I offend here, but I'll go out on a limb and take a guess that you're a younger shooter, and that's fine. I've noticed that younger folks tend to question the established norms and place less value on experience and proven technology, than the older crowds.


"What makes it so dang effective? As I mentioned earlier in this post, there are three things a bullet can do to increase its permanent wound cavity. .30 cal M2 ball really doesn't do any of them, so WHY is it effective? Again, it really makes a wound track about equivalent of a .38 wad cutter, so why is one considered the hammer of righteousness and the other a really good way to get yourself killed in a gunfight?"

Who says a 38 caliber is a good way to get killed in a gunfight?

At any rate, we're going in circles. All I can say is stop looking at "wound cavities" and start living in the real world. Or, to quote a Jimmy Stewart movie from the 1950's "...I'm only interested in results." I can't answer your question, because, to me, asking WHY 30-06/308 is better than 223 is like asking why does 2+2=4. How do you respond to a question like that?

 

[The Alaskan]

PS: Jenrick...

in reference to your comment: "...Hammer of Righteousness..."

That's awesome! I love it. If my Garand weren't a collector's piece, I'd have it laser engraved on the receiver.

Thanks!

 

[readyeddy]

Fragmentation, expansion and yaw from the bigger bullet does more damage. The difference from a 38 special is the higher velocity of the rifle round. An extreme example would be a 125 grain 308 bullet traveling at 3000+ fps.

 

[C-grunt]

He was comparing AP 5.56 to M80 7.62 ball. M995 will indeed penetrate stuff that M80 wont. Easy one would be steel plating. Considering M193 will.penetrate a level III AR500 plate that wil stop a M80 ball. And that's just plain milsurp 5.56.

 

[35 Whelen]

He was comparing AP 5.56 to M80 7.62 ball. M995 will indeed penetrate stuff that M80 wont. Easy one would be steel plating. Considering M193 will.penetrate a level III AR500 plate that wil stop a M80 ball. And that's just plain milsurp 5.56.

WHAT?!? Have you tried this?

I don't know exactly what Level III armor is, but I can tell you beyond a doubt that the green tip stuff doesn't even crater the 3/8" AR500 I shoot at 50 yds. here at the house. In fact my moron friends shoot my carbon steel gongs with their damned .223's (After I tell them not to) and while they crater it, they don't penetrate it. Again, at 50 yds.

Please read my signature.

35W

 

[The Alaskan]

ahhhhh...okay. I thought he was comparing like projectiles (at least in composition, if not in diameter ad weight.)

 

[Malamute]

Trend I see:

Jenrick: "I'm curious about the actual mechanics of this generally accepted result".

Other poster (s):" It just IS!!! Whats wrong with you? Why cant you get it through your head?

Jenrick: "I'm curious about the actual mechanics of this generally accepted result, how/why it actually does happen".

Other poster(s): "Its HISTORY for crying out loud!!! Whats so hard to understand?" (still entirely not getting the question)

Am I misunderstanding the situation here?

 

[The Alaskan]

Please read my signature.

35W

bwahahahahaha

meh, I guess that kinda goes both ways though. =(

 

[The Alaskan]

No you're not misunderstanding the situation at all. In fact, I think you did a good job summarizing the situation.

I think what is being missed, and I alluded to this earlier, is that, at least to me, this is a nonsensical question.

Much like no one would ever ask "Why does 2+2=4" (instead of say 22), I don't have an answer for Jenrick's question. And, apparently, neither does anyone else.

It doesn't matter why 2+2=4 and it doesn't matter why 30-06/308 is the Hammer of Righteousness...it just IS. =)

 

[The Alaskan]

Either that, or someone answered this question 3 pages ago when they asked "What would you rather get hit with, a pebble, or a brick?"

So I guess that is your "actual mechanics"...30 cal ammo weighs more and moves faster. Momentum = Mass x Velocity. (or something like that. I failed algebra.)

 

[The Alaskan]

My First "signature" on THR.

Just wanted to give a shout out to Jenrick for giving me the inspiration for my first signature at THR. (If not that actual signature itself. I think Jenrick is going to sue somebody for copyright infringement.)

 

[AStone]

Reading. Will respond .. after I finish this 1 lb burger.

Could take me a couple of days ...

 

[C-grunt]

WHAT?!? Have you tried this?

I don't know exactly what Level III armor is, but I can tell you beyond a doubt that the green tip stuff doesn't even crater the 3/8" AR500 I shoot at 50 yds. here at the house. In fact my moron friends shoot my carbon steel gongs with their damned .223's (After I tell them not to) and while they crater it, they don't penetrate it. Again, at 50 yds.

Please read my signature.

35W

M193 through level III AR500 steel armor (rated against M80). Velocity defeats metal better than weight. EDIT: reading your response again, you
know M193 isnt green tip, aka M855, right
https://www.youtube.com/watch?v=oMYkEMhPsO8&list=PLxe9bCDVt1x48dwyXYIViFtzwgx4W-uMC&index=2

M855A1 vs Level III AR500 steel armor. This round per the US Army testing does in fact penetrate several barriers better than M80 ball.
https://www.youtube.com/watch?v=e0gxeSpjdSk

As to your line to read your signature..... Try reading mine. Here is a couple pictures as well. Those were my two assigned weapons for my 2005 tour. A SDM-R and a M240B. I have said before, that M240B was my favorite weapon in theater. More so than the M2 I gunned a lot. The M240B was controllable, had range, and was actually very accurate.

So when I talk about the pros and cons of the 5.56 vs 7.62 and I say the 5.56 in my experience and opinion is the better RIFLE round (not machine gun) for combat, its not because Im some 5.56 fan boy. Its because Ive shot enough people with both to know their strengths and weaknesses. Both have their role and both are better than the other at that role.

 

[C-grunt]

I think I did a pretty good job of answering the OPs question with this answer.

Modern terminal ballistic research says that projectiles moving faster than 2000 FPS can produce temporary cavities large enough to cause damage outside of the wound channel caused by the bullets. M80 ball does indeed yaw, most base heavy spitzer bullets will.

Also M995 5.56 AP was made to penetrate level IV ceramic plates. Something no shoulder fired, non AP, round is going to do.

 

[35 Whelen]

M193 through level III AR500 steel armor (rated against M80). Velocity defeats metal better than weight. EDIT: reading your response again, you
know M193 isnt green tip, aka M855, right
https://www.youtube.com/watch?v=oMYkEMhPsO8&list=PLxe9bCDVt1x48dwyXYIViFtzwgx4W-uMC&index=2

M855A1 vs Level III AR500 steel armor. This round per the US Army testing does in fact penetrate several barriers better than M80 ball.
https://www.youtube.com/watch?v=e0gxeSpjdSk

As to your line to read your signature..... Try reading mine. Here is a couple pictures as well. Those were my two assigned weapons for my 2005 tour. A SDM-R and a M240B. I have said before, that M240B was my favorite weapon in theater. More so than the M2 I gunned a lot. The M240B was controllable, had range, and was actually very accurate.

So when I talk about the pros and cons of the 5.56 vs 7.62 and I say the 5.56 in my experience and opinion is the better RIFLE round (not machine gun) for combat, its not because Im some 5.56 fan boy. Its because Ive shot enough people with both to know their strengths and weaknesses. Both have their role and both are better than the other at that role.

Thanks for your service.

Not interested in the YouTube videos, as I've learned that anyone with a video camera can post anything they want...even if it's not true. Besides, since I can shoot 3/8" AR500 anytime I want with either cartridge and load (I have a range at my house), why would I watch a video of someone else doing it?

I'm very aware of the differences in the M193 and the M855 as I am in possession of both. That is why the letter "B" followed quickly by the letter "S" entered my head when you made your statement regarding the lead core M193 penetrating AR500 that defeated M80. Further fueling my doubt is the fact that I just happen to have a piece of my AR500 in the shop making some repairs to it, so I jogged out there and snapped a picture of the "damage" wrought by a few rounds from a .223 at 50 yds. I was shooting M855 and it was barely dented the metal. I measured the deepest dent and it was about .045". You're telling me a lighter lead core bullet would have created more damage??



Having owned .220 Swift's in one form or another for about 35 years, I'm patently aware of the capabilities of high velocity bullets (>4000 fps MV) and have seen bullets moving at such speeds do things that seemingly defied physics. In my younger days I thought it my duty to teach the world just what a wonderful killer of game a .22 caliber bullet moving at near 4000 fps was. And kill it did, but there's no such thing as deader and I learned the hard way that small bullets left very little margin for error where larger bullets did.

Not to be morbid, but my curiosity is overwhelming; how many humans have you killed with each bullet (M193 & M80) and how did the M80 fall short?

Having put lots of bullets from .22 to and including .45, through flesh and blood, most larger than your average domesticated biped, your stated experiences don't parallel mine.

35W (Keeping my signature)

 

[C-grunt]

The videos show just what you were saying. High velocity bullets can penetrate some stuff lower velocity bullets dont. Steel is one of those targets where velocity trumps mass. M193 at 3300ish FPS will penetrate certain steel barriers that M80 at 2800ish FPS will not.

By the way the second video is of M855A1 which is vastly different than M193 or M855 and is known as the "Enhanced Penetration Round" because the front half of the bullet is steel. Its not on the level od M995 but it definitely improves the barrier penetration capabilities of the standard grunt

Never used M193. Used M855, M856, and M262 for 5.56 and M80 ball and whatever 7.62 tracer is. I never said M80 let me down and Im pretty sure I said before that it is more powerful and performs better than 5.56. But terminal performance isnt the only factor when choosing a rifle round for combat. Weight, capacity, and recoil are also very important factors.

Known hits: 4 guys in Baghdad in 2003 while carrying a M249 SAW (M855 and M856) at a distance of roughly 75-100 meters. 1 guy in a small town north of Al Muqdadiyah in 2005 with my SDM-R (M262) at a range of a map measured 410 meters +/- 10 meters. 1 guy in Al Muqdadiyah in 2005 m(Christmas Eve to be exact) with my M240B (M80 and tracer) at a distance of about 25 meters.

Possibles: About another 10 in 2003 with my SAW and another 4-5 with my SDM-R in 2005. I shot at these guys with at least a decent sight picture but things like distance, cover, running targets, etc made the hits less likely and they were not seen on the ground.

In 2003 I was in the platoons Weapons Squad. We had 3 M240Bs, two M249s, Two guys with M203s, and my Javelin. Plus being a Mechanized unit we had Bradleys and Abrams tanks, who actually did most of the shooting. So trust me Ive seen A LOT of people killed by 7.62 Nato.

My brother in law who was a Marine 0351 in Fallujah has the same experiences and opinions as me when it comes to 5.56 vs 7.62. The 7.62 is a great machine gun round but he would rather carry a 5.56 rifle.

 

[C-grunt]

Just for clarification.... I consider the 223/5.56 to be marginal for deer. I also consider the White Tail deer to be a tougher animal than a human.

 

[Tirod]

What the .30 proponents insist in a matter of religious belief - that .30 is superior - falls apart when you take in the cartridge our soldiers were facing in the .30-06's heyday. The 8mm Mauser.

No, .30 isn't all that. 8mm will trump it in every category. So much for faith. Your belief in the cartridge isn't all that.


What .30 brings is a lot more mass, certainly in comparison to 5.56. What it doesn't do is get the shooter to try more often. Those studies were ongoing in the military after WWI and already coming to fruit with the .276 Pedersen. The thinkers in the military saw that having the ability to launch heavy projectiles out to 800m with lethal results had the unintended consequence of the shooter not liking the recoil and simply not shooting.

Study after study showed that in combat - not some mowed grass range - most soldiers preferred guns with less recoil and would shoot them. Study after study showed that most soldiers simply couldn't see the target until it got to about 125m - because said target was using every means at hand to seek cover and concealment.

It makes no difference if one bullet or the other can penetrate more - its an incremental difference when you are discussing ridgelines or armored troop transporters. They still won't penetrate, it takes a crew served weapon to do the job.

This is where the belief in the .30 falls apart - the marksman is not the answer to most of the issues he faces on the battleground, and more importantly, his choice of cartridge simply cannot meet the demands of his challenges without increasing his burden and working against him.

It's fine to trot out penetration and power, the reality is that on the battlefield, most injuries are caused by 1) artillery, then 2) hits by longer range crew served weapons, then 3) undirected hits by infantry fire the enemy walked into. Those rounds weren't intended to stop them - they didn't intend to jump into that lane of fire - it happened due to the chaos of warfare.

The simple fact is that egotism still runs rampant in cartridge selection and that doesn't get much traction when empirical numbers and coolly thought out reasoning look at the results. The soldier is just the last line of resistance - and at those distances engaging the enemy with large unwieldy guns with an overabundance of power unnecessary to his defense is a negative.

But gun owners and shooters don't look to battlefield studies or tactical success when they pick a gun and caliber - they more often choose them based on their perceived social ranking among their peers.

The .30 main battle rifle will always have it's fans, the issue is when they justify their choice by denigrating the current tactical doctrine with descriptions based on size or immaturity. It's a "poodleshooter," "pop gun," something only children should play with, as if it were best for those who aren't Real Men. Because we all know Real Men don't use them, they use Big Boy cartridges in Real Guns.

Despite our last 45 years of doing the opposite, and doing it against enemies equipped with WWII battle rifles, like the SKS.

Supporting fire, tactics and maneuver, plus simple experience on the battlefield which we are systemically handing down as fast as possible, makes the Army in the field a difficult warrior to overcome. Like in sports - we have to set up our own failure to lose.

It's not by choosing the wrong weapon or cartridge, politics certainly does play a lot into it, which is why it wasn't until the late 1950's that we returned to looking at smaller cartridges and the weapons that could shoot them. And the studies were done all over again - with the view that battlefield results would be the guideline. If it wasn't effective in combat it wasn't good enough.

.30 - ballistically - has it's advantages. More mass and frontal area. It also has disadvantages - more mass and frontal area. Looking at only the advantages and ignoring the disadvantages that go along with it is extremely selective and biased. Sure it can carry a lethal amount of power out to long ranges. No, the average soldier simply can't take advantage of it in combat when the enemy is aware of him and is shooting back. It's a niche round and mainly effective in a crew served weapon or as a sniper - both of which offset the enemy's ability to defeat it.

Absent any consideration of how a cartridge is going to be used, the discussion remains purely academic and math based. Drawing conclusions on the math and then inserting them into combat is the error. We learned that error going up against 8mm and had to come up with alternative solutions.

 

[zb338]

I talked to a lot of guys that served back in Korea where they
used the 30/06 caliber in rifles and machine guns. They said
that any enemy soldier that got hit in the chest with a .30 caliber
bullet didn't live long enough to make it to the hospital.

Zeke

 

[Corpral_Agarn]

I talked to a lot of guys that served back in Korea where they
used the 30/06 caliber in rifles and machine guns. They said
that any enemy soldier that got hit in the chest with a .30 caliber
bullet didn't live long enough to make it to the hospital.

Zeke

As apposed to what?

Weren't they pretty much only shooting 30 cal at the enemy in Korea?

I would think that a hit to the chest with a 5.56 would greatly limit your chances of survival as well.

 

[35 Whelen]

This thread has just about reached the point of irrational ramblings, but just a final thought before I make good use of the "Unsubscribe" feature...

If the .223/5.56 bullets coated with their pixie dust and unicorn feces are "all that", why are .30 caliber weapons and cartridges still in use in our military?

Signing off....

35W

 

[Don357]

My thoughts are that Jenrick (who's probably still wet behind the ears and from a urban or city area) needs to get out of the books and get onto a range, shoot some gel and see the difference. Then he will know why the .30 is better than the .223.