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How many people think pistol caliber cartridges kill better than rifle caliber cartridges

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I have first hand knowledge on GSWs. Ive seen an 18yo shot dead center chest with a 357 fmj walk out the next day with bandaids front and back. Tried to kill himself with his dads 6" colt in front of girlfriend. Ive seen multiple men riddled with 9mm fmj with very little blood loss. 3 rounds center chest with 115hp 9mm. If I can fing the xray I'll post it. Guy was in hosp 3 days total. Had a 30yo shot by a hunter in the left hip with 30/30. Most of his buttcheek was gone. Died on the table from massive blood loss. Wound was unreal. Bullet exoded after hittin pelvis. 38 wadcutter to the side of the head and guy lived. 22lr to neck doa. 22lr near the naval of a 14yo kid accidental died within 10 min in ED. 9mm through heavy clothing or fat dudes has never impressed me. Many dont make it through to the lungs.
I have no doubt about those real world situations. It's all about shot placement in MOST situations. Obviously if you hit some one with a big enough projectile at a high enough velocity (KE) it can cause enough trauma to be lethal regardless of shot placement. Not so different that a .22LR that hits a femoral artery in a leg or a .50 Cal BMG blowing your arm off...both cause blood loss.

Your examples prove that very point however that shot placement is the most critical followed second by penetration depth. Lung shots with a non-expanding handgun bullet are often not fatal if dealt with appropriately and the biggest threat is infection.

Had that .357 pierced a chamber of his heart or hit his spinal column or a large bone the story changes dramatically. Same with the guy shot in the chest. The heart is not a large target (much smaller than the head).

There are more people killed by .22LR than any other caliber in the world...simply because it's so cheap and so popular and so easy to shoot, enough shots to vital areas happen more by chance. The ratio of single shot kills relative to the number of shots fired is very low. It's just there are so many .22LR based fire arms out there.

Sounds like being fat may actually be a benefit if your get shot eh?
 

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I stick with my vote. I am the one that voted for the 5.56. I have no doubt that it is the correct answer.
 

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No problem, I'm looking to build a 5.56 upper myself. However it's purpose is as a back-up and for training purposes. You always want to have as much over-match as you can wield. Then fall back to less effective means as your best is exhausted.

Your more likely to win each encounter and get further along vs. trying to save the "best for last" that you may never get to!

There's a reason the military is so bent on finding over-match. Anything you can do that is morally justifiable to give you an edge provides a higher chance of success. You can win a thousand battles, but loose only one and it's over.

6.8 SPC is over-match to 5.56 / 5.45 / 5.8. No question about it. However given that the OP does have other over-match calibers available, it was my understanding that this is a 2nd tier gun.

And given the limits of 5.56 (barrier penetration, wounding), optimally performing loads become more critical to make it consistent and effective. That is the basis of my argument, not to avoid 5.56 altogether, but to be critical of ammunition choices.

Of those that do use 5.56 to hunt deer, hogs or for self defense, I can tell you they are NOT using 55gr or 62gr FMJ and for good reason.
 

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And for the record, no where did I suggest 9mm from an 8" barrel outperformed 300BO or 7.62x39mm. I simply stated that using a more power cartridge that the shooter isn't capable of effectively using is less optimal than using a less effective cartridge that the shooter can effectively shoot (tongue twister) because the fact still remains that #1 and #2 are the most important factors in stopping a threat.

A shot in the arm or shoulder with an expanding 300BO / 7.62x39mm from an SBR is LESS effective than a shot to the heart or head from a 124gr 9mm Hollow Point. Engaging a human opponent is a whole different ball game than a deer that just stands there until shot...so perhaps my perspective is more biased on shot placement and penetration depth than a typical hunter due to the nature of my applications.

But this is a separate discussion that's specific to the capabilities of the shooter rather than the potential of the cartridge, yet a very pertinent one and the reason the FBI, despite it's 10 year push for .40 S&W has now moved back to 9mm. The maximum effect is always a matching of the cartridge to both the shooters capabilities and the intended target. More is NOT always better.
124gr 9mm is same size (weight) bullet as 7.62x39 or a super loaded 300BS, the difference is dia and 1000fps or more in velocity.
While yes the premise that momentum matters more to penetration holds some water. the example is where you lost many. Big and somewhat slower is what is used by Dangerous Game hunters all over the world, but no one is going in with a 45LC over a 458wm.
 

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124gr 9mm is same size bullet as 7.62x39 or a super loaded 300BS, the difference is dia and 1000fps or more in velocity.
While yes the premise that momentum matters more to penetration holds some water. the example is where you lost many. Big and somewhat slower is what is used by Dangerous Game hunters all over the world, but no one is going in with a 45LC over a 458wm.
This is a very good point. Dangerous game rounds are nearly always solids/non-expanding with a relatively blunt nose, because penetration is the most important factor. The wound channel is nowhere near as wide but much longer. No one will argue and expanding, fragmenting or tumbling bullet will do major damage to a lion. However, even if you blow up a lung, a lion can still shred you to ribbons. If you take out a lung and a spine or a hip that lion is far less likely to make it to you. This is the exact same concept as barrier penetration. Some guy is hiding behind a car, you want a bullet to be able to make it to the guy. Same thing with a cape buffalo skull, you need to be able to bust through it with enough bullet left to destroy the brain or spine. Humans stand, and we are soft so deep penetration it's not as effective or important. Any projectile that expands, tumbles or fragments is likely to take us out of the fight.
 

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I should have been more detailed, the kid that shot himself in the chest with the 357 had an intervention from God. The bullet went between his lungs, under the SVC and to the right of his atrium. Doubt anyone could purposely thread a bullet through there. Prob a 1/2" window on most people. Fyi: a wad cutter does far more internal damage than a fmj 9mm. The traima to the lungs is 4 -5" plus a cut hole the size of the projectile as opposed to a hole that semi closes to less than the bullet diameter. I was shocked when we took it out. One of the guys said " what the hell kinda bullet is that?" I told him it was the same 38cal wad cutter my dad loaded us to shoot when I was a kid. We all expected a big 9mm hp with the damage when we opened his chest.
 

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Projectile design is definitely important, as a round nosed fmj (especially in pistols) seems to push things out of the way more so than an expanding or wad-cutter type. If penetration is what you want then a solid or cast bullet would be better than an expanding hp etc. but if massive trauma is whats most important and you dont care that it only penetrates 6-8" then you want the varmint round and not the banded solid.
 

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Perhaps I did not state the concepts clearly which I was trying to convey (unless your question is rhetorical). Rifle rounds have much higher KE and much higher Velocity. It's that combination that causes a massive hydrostatic pressure wave because the soft tissue can only be moved out of the way so far and stretched so far before tearing, being mostly water.

That pressure wave causes additional tearing (especially with bullet fragments that have already weakened tissue radially around the point of fragmentation), making a vastly disproportionate wound relative to the projectile size. It's that resistance to the projectile that obviously also causes the bullet to fragment, having pressure around it's frontal area, especially when they yah and have a cannelure which weakens the frontal region. When turning sideways to any degree, we now have even MORE area with pressure on it and it breaks apart.

This is one reason why fleet AOA issues caused inconsistencies in M855's fragmentation ability even at very close ranges (0 to 50 yards) with through and through hits. Because it is also velocity dependent, at intermediate distances it once again becomes a problem because now regardless of AOA, the hydraulic pressure against the projectile is no longer high enough to cause fragmentation (typically 150 yards for a M4 and about 200 yards for an M16).

That's the very reason many hand gun rounds actually penetrate deeper, because they have high momentum (heavy) and low velocity. So they do NOT create that large pressure wave (rapid transfer of energy), do not fragment and only provide in some cases mild expansion to slightly enlarge the permanent wound cavity. It is that conservation of energy that allows them to stay in motion until all of it has been transferred from the projectile to the target. The slower that process, the further it will penetrate. Rifle rounds would typically penetrate even deeper if they do not expand or fragment, but even many SBR's achieve that at closer ranges. Combine the reduced KE, momentum with still reasonable expansion and penetration suffers (unless that load is over driven in a longer barrel).

It is for that very reason you can "over drive" certain hollow points that have ideal penetration to expansion ratios but when hot loaded (+P+) to the limit, may suddenly have inadequate penetration. They expand more rapidly and to a greater degree at higher velocities, thus transferring their KE more rapidly. The problem is with handgun rounds, the additional expansion isn't really enough to overcome the tissues elasticity, but the drag is higher, so they tend to NOT create a larger wound while simultaneously suffering inadequate penetration. Kind of a sucky situation. Federal HST and Speer Gold Dot's are two of the most consistent loads for expansion, but some of the super hot +P loads over drive them and result in barely adequate penetration.

Aside from that specific instance however where you primarily changing bullet weights, taking a heavy vs a light load, the heavy load typically will penetrate deeper even if it achieves nearly identical expansion due to it's higher momentum (again, pending over expansion does NOT counteract that by increasing it's drag in target).

Momentum is thus a better predictor of penetration on average than KE pending the projectile design does not change considerably. We all know that 110gr projectiles tend to penetrate deeper than 85gr projectiles even if both are hollow points of the same over all constructions and the KE at the muzzle is the same. The combination of lower velocity (less expansion) and higher momentum both play a role, but momentum seems to more reliably predict penetration depth.

I was not in ANY way trying to argue that handgun rounds out perform rifle rounds in wounding (volume of tissue actually damaged). However compared to SBR's, many common hand gun rounds actually penetrate deeper, but have a very small permanent wound cavity, thus making them less effective. That is due to their high momentum to low expansion properties.

I am not arguing with these studies on wounding: see attachments. I'm simply suggesting momentum is more useful for determining weather a load is likely to have adequate penetration than just it's KE which people often see as a necessity for deep penetration with heavy loads.
Terminal ballistics are dynamic and can be very baffling. There are a lot of factors at work and there is no simple formula that will come close to explaining it. I'm sure someone could come up with a formula, but it would be very long with a lot of variables. Momentum and kinetic energy are used because the weight and speed of a bullet are major factors, but also because they're very simple to work with.

I mean no disrespect, I am trying to clarify things a bit, some of your explanations are comparing half of an apple to half of an orange and then adding some bananas and grapes making for a fruit salad explanation.

Momentum= MV
Kinetic Energy= 1/2MV²
Pressure is force applied over an area. P=F/A
Hydro neans fluid. Static means still. Dynamic means changing.
Our old buddy Sir Ike Newton's, explanation in regards to Conservation of Eomentum and Energy: An object in motion tends to stay in motion until acted upon by another Force. He also states, For every action there is an equal and opposite reaction.

In both formula, Momentum and Kinetic Energy, speed the multiplier. Speed is more important in kinetic energy because velocity is squared and the mass is halved. Momentum is what keeps the bullet moving. Kinetic energy is the stored energy of the moving bullet and a good indicator of what the bullet is capable of doing when it strikes a target.

Handgun bullets do not penetrate deeper simplely because they are moving slower. They penetrate deeper because they have not used a lot of energy on expansion or fragmentation, because they simply do not possess the energy, and have the structural Integrity, to expand and penetrate. The +P+ handgun bullets will expand or fragment violently with very little penetration, because they now have enough speed to contribute to the energy and overcome the strength of their construction. Fast moving rifle bullets that have lower momentum, but don't spend energy on expansion or fragmentation, will penetrate extremely deeply.

A tumbling bullet may fragment because force is applied to places it was not designed to withstand. When a bullet turns sideways to its path of travel pressure is not increased, it is decreased because you now have a larger surface area. A bullet traveling sideways, or tumbling, creates a larger wound channel simply because it is more surface area being forced through tissue.

Fired from a SBR:
55 gr 5.56mm @ 2300 ft/s
Area: 0.039in²
Momentum: 56 slug ft/sec
Kinetic energy: 646 ft·lb

147gr 9mm @ 1200 ft/s
Area:0.099in²
Momentum: 78 slug ft/s
Kinetic energy: 470

The 9mm has a 60% greater area but only 25% more Momentum. The 5.56mm has 27% more energy and about double the pressure. The instant the bullets strike the target all of these calculations change. Depending on how the bullet is constructed (what it is made of as well as its shape) and what the target is made of will determine what happens next. These forces will be easy to calculate only if the bullets were and stayed cylinder shaped like a wadcutter. Throw in a round or very aerodynamic tip and calculations get much more difficult. Add bullet expansion, fragmentation and a tumble and you'll wear your calculator out. Xfrog has witnessed and explain the difference in wound channels between an aerodynamic bullet and a wadcutter.

Centrifugal Force= MV²/r

Another important and often overlooked force is the energy in centrifical force of the spinning bullet. Centrifugal force is a form of kinetic energy. Rifle bullets spin faster, not just because they need more twist to stabilize their longer length, but because they're traveling faster. Centrifical Force assist in bullet expansion and fragmentation. It can be a major factor in temporary and permanent wound channels. X-Man has documented some of the effects centrifugal force has on wound channels. I believe centrifugal force contributes to, "...a vastly disproportionate wound relative to the projectile size". A larger bullet will have a larger wound channel than a smaller diameter bullet. An expanded bullet will have a larger wound channel than a non-expanded bullet. An expanded bullet that fragmentation, will have an even larger wound channel.

All of these formulas are taken in a static moment of time. Terminal ballistics are very dynamic, they can be calculated moment by moment with these formula, but with every consecutive moment, a new set of calculations is needed.
 

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Discussion Starter #89
Exactly why I laugh when the Grendel guys say bullets with a higher SD penetrate deeper without taking any of that into consideration.
 

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124gr 9mm is same size (weight) bullet as 7.62x39 or a super loaded 300BS, the difference is dia and 1000fps or more in velocity.
While yes the premise that momentum matters more to penetration holds some water. the example is where you lost many. Big and somewhat slower is what is used by Dangerous Game hunters all over the world, but no one is going in with a 45LC over a 458wm.
Simple stated, with the same cartridge, looking at the projectiles momentum vs. it's KE will give you a better idea as to weather the load will provide good penetration or not. That's literally all I'm trying to say. But yes, we have a lot of variables.

1. Expansion. If momentum is the same, the more the expansion the less the penetration.
2. Provided expansion is the same, greater momentum will provide more penetration.
3. Expansion counteracts momentum because it increases the rate if KE transfer to the target.
4. KE is a very poor predictor of performance overall, yet is often obsessed over. It does not provide any insight into penetration, expansion or terminal performance. Sure, you need enough KE to transfer to the target, but 500 ft-lbs vs. 550f ft-lbs is a pretty meaningless difference in the real world. Performance predictions are better served via momentum, velocity and bullet construction.
4. The best loads for medium game are TYPICALLY high expansion combined with high momentum, you get a reasonably large wound channel that also goes fairly deep vs. a low momentum load that might provide a larger wound channel but sub-par penetration or a very small wound channel with very high penetration. One can approximate what to expect in terms of penetration via looking at momentum rather than KE of a given load.

I'm not in any way trying to argue that we should rely solely on momentum because there are many other variables to consider. But, it's a useful tool in the tool box and more useful than just trying to get high KE numbers. Most 5.56 guys obsess over KE for some reason, but ignore momentum and wonder why so many 5.56 loads fail to perform as intended. It's one reason why the military has moved to heavier loads for 5.56 vs. light loads despite having the same KE at the muzzle.

But I'm not trying to start some long debate, just brining a different angle of perspective because conventional thinking for some reasons seems to overly focus on a projectiles KE (especially in those dumb comparisons of 6.5G vs. 6.8 SPC in the 300 to 600 yard range). Yet 6.8 performs more consistently on target despite slightly lower KE...because the projectile diameter to length ratio provides for more ideal characteristics with available projectile designs, this is particularly notable with barrier blind performance vs. direct hits on the target (in which both are similar).
 

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Simple stated, with the same cartridge, looking at the projectiles momentum vs. it's KE will give you a better idea as to weather the load will provide good penetration or not. That's literally all I'm trying to say. But yes, we have a lot of variables.

1. Expansion. If momentum is the same, the more the expansion the less the penetration.
2. Provided expansion is the same, greater momentum will provide more penetration.
3. Expansion counteracts momentum because it increases the rate if KE transfer to the target.
4. KE is a very poor predictor of performance overall, yet is often obsessed over. It does not provide any insight into penetration, expansion or terminal performance. Sure, you need enough KE to transfer to the target, but 500 ft-lbs vs. 550f ft-lbs is a pretty meaningless difference in the real world. Performance predictions are better served via momentum, velocity and bullet construction.
4. The best loads for medium game are TYPICALLY high expansion combined with high momentum, you get a reasonably large wound channel that also goes fairly deep vs. a low momentum load that might provide a larger wound channel but sub-par penetration or a very small wound channel with very high penetration. One can approximate what to expect in terms of penetration via looking at momentum rather than KE of a given load.

I'm not in any way trying to argue that we should rely solely on momentum because there are many other variables to consider. But, it's a useful tool in the tool box and more useful than just trying to get high KE numbers. Most 5.56 guys obsess over KE for some reason, but ignore momentum and wonder why so many 5.56 loads fail to perform as intended. It's one reason why the military has moved to heavier loads for 5.56 vs. light loads despite having the same KE at the muzzle.

But I'm not trying to start some long debate, just brining a different angle of perspective because conventional thinking for some reasons seems to overly focus on a projectiles KE (especially in those dumb comparisons of 6.5G vs. 6.8 SPC in the 300 to 600 yard range). Yet 6.8 performs more consistently on target despite slightly lower KE...because the projectile diameter to length ratio provides for more ideal characteristics with available projectile designs, this is particularly notable with barrier blind performance vs. direct hits on the target (in which both are similar).
If anything, I'm more of a momentum guy, I like big bullets, I cannot lie. So I understand your basic premise. I like big bullets, but l want 'em served hot. Hot= KE. Your obsession on momentum is the same thing as other obsession on kinetic energy. Don't get me wrong, I'm not trying to shoot holes in what you are saying. I'm trying to clear things up. Some of your statements are unclear and contradictory.

Both forces, momentum and kinetic energy, are important and you realy can't have one without the other. In one of your points you say, "Performance predictions are better served via momentum, velocity and bullet construction." Momentum with an extra serving of velocity is pretty much kinetic energy. Just saying...
Both forces are rather irrelevant if they are not applied. Momentum is important for predicting penetration. KE is a better indicator of how the bullet should preform. Mechanical and Design engineers use KE, more so, then momentum when factoring structural integrity. Bullet manufacturers are more apt to use kinetic energy when designing terminal performance. I think people (people on this forum anyway) are intelligent enough to determine what bullet they need when given caliber, weight, speed and energy.
 

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Under 150 yards I'll stick with my .458 socom, super or sub.
 

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A tennis ball, a 22 long rifle and a golf ball walk into a bar...

Tennis ball: .127 lbs, 232 ft/s, 106 ftlb
22 LR: .006 lbs, 1085 ft/s, 105 ftlb
Golf ball: .101 lbs, 264 ft/s, 109 ftlb
They all have nearly the same energy. Let's look at their momentum numbers.
TB: 29.46 lbft
LR: .6.51 lbft
GB: .26.67 lbft
I know what you're thinking. Blessed Mother of Acceleration, a Tennis Ball has 10% more momentum than a Golf Ball?

IF we compare barrels 7-8" long (obviously all subguns 15" overall length) and shoot each 9mm 124gr (apx 1375fps), 300BO 110gr(apx2000fps), and 5.56 62gr(apx2350fps) which comes out ahead? I know the 300 using 110gr bullets will have more energy but energy isn't everything. To make things close lets say all bullets are expanding hollow points.
A 9mm Parabellum, a 300 BlackOut, and a 5.56 NATO get into a gunfight...

Caliber, Weight, Volosity, Momentum, Kenetic Energy
9mm 124gr, 1375 ft/s, 24.3, lbft, 520.5 ftlb
300BO 110gr, 2000 ft/s, 31.4 lbft, 976.8 ftlb
5.56 62gr, 2350 ft/s, 20.9 lbft, 760.1 ftlb
Just looking at Momentum, it appears the tennis and golf balls have, well, got some balls after all... Except, bringing tennis and golf balls to a gunfight is much worse then bringing a knife to a gunfight. People will take cover if you shot back, any gun is better than no gun.
 
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Discussion Starter #96
Believe it or not I'm going with the 300 subsonic 208s and supersonic 110 Varmageddon. Subsonic with more weight than a 9mm 147 at apx the same vel and 110s at near twice the vel of 115 9mms.

300 VS 5.56 twice the weight bullet only 200fps slower.

If I have to use a full sized AR15 receiver I want more than a pistol caliber in it. I have 10mm pistols.
 
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