Kachok
Member
There seems to be much misunderstanding reguarding terminal ballistics in our little community, and everwhere else for that matter, so I would like to open a discussion covering the facts and fiction of terminal performance. I am no PhD in terminal ballistics, but I have studied it for many years and understand it well enough to cover the basic points, feel free to debate me on any point you like.
First things first, our objective. A clean kill. There are four basic types each a little different, and some work better with different bullet construction.
Shock kill: This is the classic bang flop, often considerd ideal performance. This is not an exact science, it appears to be the result of a concussion like effect, usualy the result of faster moving, faster expanding bullets striking the lungs. Not actualy an instant kill, but they bleed out unconscious, just as good. While shock kills are great, never use varmint or similar high fragmentation bullets to try to maximize this, shock kills are not to be counted on, and if you don't drop them instantly and don't have adaquate penatration to reach the vitals, meaning you just mortaly wounded an anamal that you will likely never find.
Mobility Kill: usualy the result of the classic high shoulder shot. They die from blood loss, but without the ability to run no tracking should be needed. Since this shot often encounters several bones and thick muscle this is genraly best with a harder constructed, larger caliber bullet
CNS Kill. This one is a no-brainer, any bullet that can penatrate the skull or spine is capable of a true instant kill.
Exsangunation: Almost all archery kills are a result of rapid blood loss, many slower moving/expanding bullets through the lungs won't bang flop them, but this rapid blood loss will make sure they don't get far.
Fragmentation
This one is complex, because there are different grades of fragmentation. Some bullet companies would have you beleve that any fragmentation is always bad, this is not true. Fragmentation can be a wounderful way to apply more of the bullets potential energy to the target this is especaly true of thin skinned game where penatration is often not a major issue. Some bullets will fragment into larger pieces creating worthwhile secondary wound cannals, others tend to have a smaller particle fragmentation that don't make make noticable secondary wounds but still make for an improved shock cavity due to the greater surface area and applied energy. Now I consider the larger type fragmentation to be highly effective, not just applying pressure to sourounding organs but actualy puncturing them. Some people even go as far as to heat and rapidly cool their bullets in an attempt to make their lead more brittle so it will break off in larger pieces.
Personal note: As long as I am still getting full penatration I am absolutly fine with my bullets slinging fragments outward through the other vital organs/arterys, my ballistic tips seem to do this very well, I find fragments in the lining of the rib cage so I say my fragments are being highly effective.
A quick note about fragmentation and any deformation of bullets, the deformation itself absorbs some of the bullets energy.
Hardcast bullets
Lots of confuson about this one. Hardcast is genraly used to describe a cast bullet that does not expand, the lead is mixed with tin to make it rather hard, since these expend little to no energy on deformation, and experence virtualy no bullet yaw/deflection thanks to their broad flat nose, they are capable of remarkable and very streight penatration. The key to properly applying the bullets energy to the target is the large meplet (flat point of the bullet) Hardcast performance lends itself to larger caliber bullets usualy .357 and up. This is an ideal bullet for a pistol or carbine defence bullet for bear since that exellent penatration makes for very disproportiante killing power. Performance is near identical to the jacketed FP solids used in Africa. While the wound canal is very deep, it however is not as wide as a soft point or hollow point, meaning it is not the ideal for deer, but it will do the trick for sure. Very little meat damage with this type of bullet.
Flat point vs round nose vs pointed bullets
Flat point: The least aerodynamic of the bunch but it does hit slightly harder since it basicly has a head start on expansion, it is also the least likley to have any deflection on heavy bone. Best bullet in the brush.
Pointed bullet: The best external ballistics by far, but the most likely to deflect on brush in flight, and deflect internaly on bone though this is very rare. The natural slight dealy in expansion does mean that slightly less energy is expended on the hide going in.
Round nose: Splits the difference between the pointed and flat nose. Does not hit as hard as the flat nose but harder then the pointed for sure.
Speed and penatration: Many of us are still under the impression that our soft point bullets will drive deeper of we push them faster. This is absolutly wrong, faster moving means faster expanding and more weight loss through fragmentation, and possably bullet seperation. This equals less penatration on game though the wound tract will be wider. This has been tested several times, and only premium bullets such as the Partition will maintain penatration at higher speeds.
Bonded bullets: the biggest trend in bullets today, a good idea for CXP3 class game, but a really silly idea to market it to deer hunters, no need to bond bullets for whitetail IMHO, as I said before some fragmentation can be useful as long as it does not compromise penatration. While I do load some bonded bullets they have little to no advantage over the partitioned bullets we have had for decades. A good Nosler Partition expands fast and retains about 3/4 of it's weight, last I checked that was on par with the best bonded bullets. The only advantage I can see is that some of the bonded bullets are poly tiped boat tails which have better BCs then Partitions or A-Frames.
Formulas: there are countless formulas that attempt to give a basic prediction of terminal performance, some are OK and others don't apply in this universe, here are the main ones.
Pure Energy formula. This one gets an F, it is flawed by it's very nature. Energy is the potential of work not work itself. Our prey is a three dimensional object we cannot aproach it with a two dimensional formula. Just for a funny comparison. Take two 500hp hotrods of equal weight, put slim street tires on one and low pressure bias-ply drag slicks on the other. now drag race them. That is no contest. Same "energy" but very very different results in the real world. The 223 Rem has more energy then a 454 Casull, the 223 was designed to wound a human and the 454 was designed for very big game hunting, and is commonly used by guides for bear defence.
OGW formula. Better but no cigar this one gets a C, no adjustment for the bullets caliber, but at leased it does account for the weight of the bullet used.
TKO formula. Absolutly the worst formula ever applied to ballistics, I would give it an F but that would be too good for it. The total opposite of the OGW formula, in TKO it is all about caliber, according to the TKO formula a 90mph fastball is twice as deadly as a 460 Wby Magnum, and a thrown beach ball is more deadly then a .50 BMG!!
If you put any stock on formulas check out the one that Chuck Hawks wrote, while I don't totaly agree with the values assigned to each factor at least it does take each of them into account in a reasonable fashon.
Caliber sectional deansity and penatration
It is no secret, heavier for caliber bullets tend to penatrate deeper then lighter ones, but if you compare larger and smaller calibers of the same sectional density you will find that the larger caliber will drive deeper, so even if your 223 can shoot .228 SD bullets don't expect them to penatrate as deep as a 150gr 30 cal of the same construction.
I will wright more later my fingers need a break.
First things first, our objective. A clean kill. There are four basic types each a little different, and some work better with different bullet construction.
Shock kill: This is the classic bang flop, often considerd ideal performance. This is not an exact science, it appears to be the result of a concussion like effect, usualy the result of faster moving, faster expanding bullets striking the lungs. Not actualy an instant kill, but they bleed out unconscious, just as good. While shock kills are great, never use varmint or similar high fragmentation bullets to try to maximize this, shock kills are not to be counted on, and if you don't drop them instantly and don't have adaquate penatration to reach the vitals, meaning you just mortaly wounded an anamal that you will likely never find.
Mobility Kill: usualy the result of the classic high shoulder shot. They die from blood loss, but without the ability to run no tracking should be needed. Since this shot often encounters several bones and thick muscle this is genraly best with a harder constructed, larger caliber bullet
CNS Kill. This one is a no-brainer, any bullet that can penatrate the skull or spine is capable of a true instant kill.
Exsangunation: Almost all archery kills are a result of rapid blood loss, many slower moving/expanding bullets through the lungs won't bang flop them, but this rapid blood loss will make sure they don't get far.
Fragmentation
This one is complex, because there are different grades of fragmentation. Some bullet companies would have you beleve that any fragmentation is always bad, this is not true. Fragmentation can be a wounderful way to apply more of the bullets potential energy to the target this is especaly true of thin skinned game where penatration is often not a major issue. Some bullets will fragment into larger pieces creating worthwhile secondary wound cannals, others tend to have a smaller particle fragmentation that don't make make noticable secondary wounds but still make for an improved shock cavity due to the greater surface area and applied energy. Now I consider the larger type fragmentation to be highly effective, not just applying pressure to sourounding organs but actualy puncturing them. Some people even go as far as to heat and rapidly cool their bullets in an attempt to make their lead more brittle so it will break off in larger pieces.
Personal note: As long as I am still getting full penatration I am absolutly fine with my bullets slinging fragments outward through the other vital organs/arterys, my ballistic tips seem to do this very well, I find fragments in the lining of the rib cage so I say my fragments are being highly effective.
A quick note about fragmentation and any deformation of bullets, the deformation itself absorbs some of the bullets energy.
Hardcast bullets
Lots of confuson about this one. Hardcast is genraly used to describe a cast bullet that does not expand, the lead is mixed with tin to make it rather hard, since these expend little to no energy on deformation, and experence virtualy no bullet yaw/deflection thanks to their broad flat nose, they are capable of remarkable and very streight penatration. The key to properly applying the bullets energy to the target is the large meplet (flat point of the bullet) Hardcast performance lends itself to larger caliber bullets usualy .357 and up. This is an ideal bullet for a pistol or carbine defence bullet for bear since that exellent penatration makes for very disproportiante killing power. Performance is near identical to the jacketed FP solids used in Africa. While the wound canal is very deep, it however is not as wide as a soft point or hollow point, meaning it is not the ideal for deer, but it will do the trick for sure. Very little meat damage with this type of bullet.
Flat point vs round nose vs pointed bullets
Flat point: The least aerodynamic of the bunch but it does hit slightly harder since it basicly has a head start on expansion, it is also the least likley to have any deflection on heavy bone. Best bullet in the brush.
Pointed bullet: The best external ballistics by far, but the most likely to deflect on brush in flight, and deflect internaly on bone though this is very rare. The natural slight dealy in expansion does mean that slightly less energy is expended on the hide going in.
Round nose: Splits the difference between the pointed and flat nose. Does not hit as hard as the flat nose but harder then the pointed for sure.
Speed and penatration: Many of us are still under the impression that our soft point bullets will drive deeper of we push them faster. This is absolutly wrong, faster moving means faster expanding and more weight loss through fragmentation, and possably bullet seperation. This equals less penatration on game though the wound tract will be wider. This has been tested several times, and only premium bullets such as the Partition will maintain penatration at higher speeds.
Bonded bullets: the biggest trend in bullets today, a good idea for CXP3 class game, but a really silly idea to market it to deer hunters, no need to bond bullets for whitetail IMHO, as I said before some fragmentation can be useful as long as it does not compromise penatration. While I do load some bonded bullets they have little to no advantage over the partitioned bullets we have had for decades. A good Nosler Partition expands fast and retains about 3/4 of it's weight, last I checked that was on par with the best bonded bullets. The only advantage I can see is that some of the bonded bullets are poly tiped boat tails which have better BCs then Partitions or A-Frames.
Formulas: there are countless formulas that attempt to give a basic prediction of terminal performance, some are OK and others don't apply in this universe, here are the main ones.
Pure Energy formula. This one gets an F, it is flawed by it's very nature. Energy is the potential of work not work itself. Our prey is a three dimensional object we cannot aproach it with a two dimensional formula. Just for a funny comparison. Take two 500hp hotrods of equal weight, put slim street tires on one and low pressure bias-ply drag slicks on the other. now drag race them. That is no contest. Same "energy" but very very different results in the real world. The 223 Rem has more energy then a 454 Casull, the 223 was designed to wound a human and the 454 was designed for very big game hunting, and is commonly used by guides for bear defence.
OGW formula. Better but no cigar this one gets a C, no adjustment for the bullets caliber, but at leased it does account for the weight of the bullet used.
TKO formula. Absolutly the worst formula ever applied to ballistics, I would give it an F but that would be too good for it. The total opposite of the OGW formula, in TKO it is all about caliber, according to the TKO formula a 90mph fastball is twice as deadly as a 460 Wby Magnum, and a thrown beach ball is more deadly then a .50 BMG!!
If you put any stock on formulas check out the one that Chuck Hawks wrote, while I don't totaly agree with the values assigned to each factor at least it does take each of them into account in a reasonable fashon.
Caliber sectional deansity and penatration
It is no secret, heavier for caliber bullets tend to penatrate deeper then lighter ones, but if you compare larger and smaller calibers of the same sectional density you will find that the larger caliber will drive deeper, so even if your 223 can shoot .228 SD bullets don't expect them to penatrate as deep as a 150gr 30 cal of the same construction.
I will wright more later my fingers need a break.
