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The Effects Of The Meplat On Terminal Ballistics
By Nathan Foster
The word meplat is a term used in ballistics terminology that has survived from a bygone era. The word itself is a french noun which means 'the flat of' and in ballistics it refers to the tip of a projectile. Meplat is not an adjective, it does not describe the shape of the tip or diameter in any way. Our current term could easily have been 'tip' or 'point' or even 'Fred' but instead, ballistic engineers of the world use the word meplat. The French were very much at the cutting edge of ballistics during the 19th century and the word meplat has survived out of an unconcious respect for these early pioneers. The term mostly likely stems from the days when all conical projectiles had flat points. The front was therefore called the flat and the rear dubbed the heel. Nevertheless, do not be confused, the word meplat simply means 'tip' in todays terms.
As most will guess, the shape of the meplat (tip) has a great effect on external ballistics (how the projectile flies through the air). The shape can also have an effect on terminal ballistics and performance with regard to projectile energy transfer on game, projectile expansion and stress to the projectile during this rapid change in medium. Put simply, a wide flat meplat projectile has far greater potential to transfer its energy immedietly upon impact than a sleek pointed projectile when bullet construction of both designs is equal.
The differences become even more pronounced when using solid, non expanding bullets, whether they be constructed of hard cast lead or full metal (copper) jackets. Unfortunately, a wide flat pointed meplat can also handicapp a projectiles potential trajectory as well as a huge loss in velocity and energy at moderate to longer ranges which can inturn result in low energy transfer.
Ideally, to fully utilise a wide, flat meplat projectile, it needs to be used in firearms that are designed for close range work or- in cartridges which already have such low velocity, that trajectory is not greatly effected by bullet meplat design.
Historically, U.S Gun writer Elmer Keith was the first hunter to both study and publish the effects of a wide, flat meplat, non expanding projectile used on game. There were definitely other hunters and ballisticians experimenting before him but it was Keith and his tenacious nature that made the wide, flat meplat into a 20th century issue. Keith pioneered the design of a flat point 250 grain .44 calibre hard cast lead pojectile for his .44 special revolver in 1926 with results that would forever shape his opinions on hunting bullet design and forever influence his staunchest fans. Yet today, more than 80 years later, the subject of metplat shape and surface area is largely untapped
In plain terms, a wide flat pointed solid non expanding bullet, even if driven at handgun velocities, creates disprortionate to calibre wounding where a pointed, non expanding bullet would create a calibre sized wound. It is this dis-proportinate to calibre wounding that is of most interest to the hunter as it is this mechanism that promotes fast clean killing.
The physics involved in wide/ flat meplat wounding are very simple, the flat point meets huge resistance on impact causing the water in flesh to be forced violently away from the path of the bullet, this in turn results in broad wounding. At velocities above 1700fps and using a wide calibre, the .45-70 (.458") which this article is focused around, entry wounds using the widest possible meplat may be up to an inch in diameter with the wound channel slightly larger and remaining the same diameter for several feet. This opens up both the possibility of both broad wounding with solid projectiles combined with penetration not normally available with expanding type projectiles.
At this point it must be noted that, the higher the impact velocity, the greater the resistance. This occurs simply because the water molecules of the animal, cannot move away from the flat point bullet at relative speeds. So as velocity is increased, wound channels increase in diameter however penetration may not necessarily be deeper due to increased resistance at the target. Pointed FMJ projectiles do not seem to show much difference in wounding or penetration at varied velocities. As an example, a 147 grain 7.62 FMJ projectile fired from a .300 Win mag creates the same size permanent wound cavity as it does when fired from a .308 Win rifle. Some extra bruising does occur throughout the lungs however the actual speed of killing remains unchanged and kills with this projectile on medium game are generally slow.
Oddly, although entry wounds with wide flat meplat bullets are almost always large, non expanding bullets of this style do not seem to produce hydrostatic shock at the typically low muzzle velocities produced by big bore rifle and handgun cartridges. By hydrostatic shock, I mean the ability of the projectile to send a shock wave through the ribs and into the spine with such speed that the central nervous system shuts down the brain (temporary coma) during which time the vitals bleed out before the animal regains conciousness, giving the illusion that it has died 'instantly'.
Due to the fact that slow, non expanding wide, flat meplat projectiles do not produce any shock effect whatsoever, when using such bullets on dangerous game, hunters are advised to expect clean but delayed kills, a potentially deadly situation. Flat meplat non expanding bullets definitely give optimum results when striking major bones. When bones are hit, wound channels change from being consistant 1 to 2" wide wound channels to much more dramatic wounding. When this type of bullet strikes bone, the fragments that separate tend to be very large and incapacitating.
On average, again using the .45-70, wound channels created by flat meplat non expanding projectiles are about four times the size of the original .458" calibre hard cast bullet however expanding projectiles in .45-70 will normally produce internal wounds twelve times their original bullet diameter at close ranges and in high velocity loadings. Needless to say, expanding bullets are capable of producing faster kills. The use of a flat meplat non expanding bullet therfore requires careful consideration.
As stated, wide, flat meplat non expanding projectiles are typically slow or 'delayed' killers, even with good shot placement. This can pose serious problems when hunting large dangerous game. Worse still, in a moment of intense stress such as during a charge, poor shot placement by the hunter may lead to minimal wounding where a premium controlled expanding bullet may have been capable of more devastating wounds. It is a tough call, on frontal shots, the flat meplat non expanding projectile driven at moderate velocities, even if missing the vitals or forwards locomotive muscles and bones, still has the potential to smash pelvis and rear leg bones. Several reports indicate that hunters have indeed anchored large heavy animals in this way.
There is not only great room for experimentation with wide meplat bullets, but also expanding wide meplat bullets, an area which most manufacturers have yet to tap into. Authorities on the subject of wide meplats generally view .300" as being the minimum and .360" being the maximum practical width for meplats of .458" calibre. These measurements prove true when tested on game and the difference that an .060" (1.5mm) increase in meplat width makes to wounding and fast killing is often dramatic.
Below are a series of photos taken from a simple days experimentation with the .45-70. The game hunted on this occasion were simply feral billy goats due to the fact that it allowed me to repeat tests over and over in a semi controlled environment- close range bush hunting where the abundance of game allowed me to take identical shots throughout a series of gullies. Average body weights for these animals was 50kg (110lb) and all animals were shot when relaxed, none were adrenalised before the shot.
The projectile used in the experiment was the Speer 400 grain flat soft point, a very good allrounder for a huge variety of game including light/ lean game up to bodyweights of around 320kg (700lb). What made this experiment interesting is that animals were taken with the Speer bullet fired backwards as well as forwards. Kids, don't try this at home. While the Speer is one of the few projectiles which already offers a generously wide/ flat meplat, firing it backwards offered the maximum width meplat possible for the .45-70. The rifle (a custom bolt action) was also tested for accuracy and surprisingly, the backwards Speer grouped well and showed no signs of instabilty when observing the uniformity of bullet holes through paper.
The purpose of these experiments was really to determine speed of killing. In recent years there has been a lot of argument throught various public hunting forums as to the effectiveness of a wide flat meplat bullet travelling at low velocity for use on dangerous game in comparison to both a low velocity expanding projectile and at the other extreme, high velocity big bores such as the .460 Weatherby. Each of these has its strengths and weaknesses. The most important factor is that the hunter be provided with correct information as to what to expect when each load is used on game and how to utilise projectiles, exploiting the strengths of the projectile designs.
For my own part, I much prefer the extremes, using a high velocity big bore. I am not so much a fan of clean but slow kills, regardless of deep penetration. I have used the .45-70 and the 400 grain Speer to take wild cattle but much prefer something a whole bunch faster. High velocity and careful shot placement gives me great satisfaction but I am also aware that penetration may be sacrificed on angling shots. For others, a classic big bore cartridge from yester year is far more thrilling to use than my latest ten million magnum. Variety is certainly the spice of life.
As for wide, flat meplats in small bores, the greatest problem with wide meplats in the small bores is that ballistic co-efficients are greatly reduced, especially with regard to wind drift. Such changes tend to handicapp otherwise flat shooting cartridges with the negatives outweighing any other benefits. Secondly, most small bores have high velocity in their favor, a major proponant in wide wound channel creation negating any need for increased performance. Perhaps the only advantage of using wide meplat non expanding projectiles in high velocity small bores would be in the design of full metal jacket projectiles in 7mm and .30 calibre for follow up shots on large game. In military ammunition, a small flat point rather than a fully pointed FMJ jacket does make a notable difference in stopping power, the ramifications are obvious.
Some examples of flat meplats disscussed throughout the small bore texts of the book Hunting cartridges of the World include- the Norma Vulcan in 6.5mm, 7mm and .30 calibre along with several brands of flat point .30-30 bullets. Of these, the Vulcan in all calibres and the .30-30 Sierra projectiles showed very good results.
Wide meplats really start to become more and more useful in the .358" calibre and upwards. Many medium bores are utilised at limited ranges of up to 200 to 250 yards and in such cases, the poor BC's created by wide meplats is of little handicap. By simply changing from a pointed soft point to a round nose soft point, many cartridges become fast killers on light or lean game where before the bullet may have carried too much momentum, failing to impart its energy. Results of the change in bullet style in the medium bores are often dramatic on all manner of game. That said, only a very few, mostly custom bullet makers, offer true flat point medium bore projectiles. Most manufacturers offer round nose bullets, nevertheless, the Woodleigh Welcore, mentioned throughout the medium bore texts, is a good example of a fast killing round nose bullet in comparison to its pointed counterpart. Both of the Woodleigh designs have their strengths which are explained in the medium and big bore texts.
As discussed, Elmer Keith was one of the very few hunter/ researchers that experimented with wide meplats in large calibres. Keith's work revolved around experiments in the calibres .38 (.357"), .44 (.430") and .45 (.451") with non expanding bullets. Very few others have experimented with big bore wide meplats, most notably Garret Cartridges inc, experimenting with both .430" and .458" calibre bullets while Lyman, Lee and RCBS offer Keith style bullet moulds. Speer are the only manufacturer to offer a wide meplat jacketed soft point bullet which comes in the form of the .45-70 400 grain jacketed flat point. Apart from this, the market remains open to the development of wide, flat meplat expanding soft nose bullets.
For those who wish to use a hard cast, non expanding, wide meplat big bore bullet for hunting large, heavy bodied dangerous game, shot placement is the key to optimum results. The hunter must attempt to destroy the autonomus plexus of game if possible, with the first shot. For many hunters, this is not a natural point of aim. The autonomus plexus is located at the junction of the heart and lungs in all mammals and viewed broad side, it is located at the ball joint intersection of the scapula and humerus bones. This joint is slightly forwards of the line of the front leg. That said, this point of aim is only applicable for broadside shots. Front on, the autonomus plexus is located at the center of the chest but slightly high, from quartering angles, the hunter must be able to visualize the autonomus plexus and aim shots accordingly. For newer hunters, performing these mental checks in the field can end up overwhelming, resulting in a generalized chest shot. The only way to avoid this, prior to a big game hunt, is to practice over and over, either mentally (visualization) or when hunting lesser game or even on small game, using a .22lr.
More information on game anatomy and killing can be found within the TBR knowledge base game killing text.
In the photo below, I have shot a dog tucker Angus cattle beast with the intention of breaking the front leg and destroying the autonomus plexus however I missed my point of aim by quite a margin. Point A is where my bullet hit versus B, the intersection of the humerus and scapula. I am holding the leg at an angle to show that the humerus bone is broken.
Below, the same beast, cut open, showing the layout of the vital organs (while a smear of beef fat on the camera lens has pretty much ruined any chance of clearer photos). The animal was slightly quartering on to me, the bullet struck the foreleg, passed through point A (top of the heart) and exited just behind the off shoulder. Point B shows the location of the autonomus plexus relative to the angle I was shooting from. Very little wounding can be seen due to the bullet style I used, a prototype GS Custom homogenous copper pointed bullet in a .375 RUM which after expansion, was somewhat similar to a hard cast wide meplat bullet. This bullet style combined with my shot placement, make it appear as though only a small degree of wounding has occured. Nevertheless, the top of the heart was severed along with good wounding through the offside lung. Death occurred in a matter of seconds. The rifle in question was built by NZ gunsmith Arthur Cleland and is a very accurate rifle.
Disclaimer/ WARNING: The views and opinions expressed in this article are solely those of the author and are not endorsed by any manufacturers. Terminal Ballistics Research and the author take no responsibility for the use or misuse of any views, opinions or information expressed in this article.
Some history
The word meplat is a term used in ballistics terminology that has survived from a bygone era. The word itself is a french noun which means 'the flat of' and in ballistics it refers to the tip of a projectile. Meplat is not an adjective, it does not describe the shape of the tip or diameter in any way. Our current term could easily have been 'tip' or 'point' or even 'Fred' but instead, ballistic engineers of the world use the word meplat. The French were very much at the cutting edge of ballistics during the 19th century and the word meplat has survived out of an unconcious respect for these early pioneers. The term mostly likely stems from the days when all conical projectiles had flat points. The front was therefore called the flat and the rear dubbed the heel. Nevertheless, do not be confused, the word meplat simply means 'tip' in todays terms.
As most will guess, the shape of the meplat (tip) has a great effect on external ballistics (how the projectile flies through the air). The shape can also have an effect on terminal ballistics and performance with regard to projectile energy transfer on game, projectile expansion and stress to the projectile during this rapid change in medium. Put simply, a wide flat meplat projectile has far greater potential to transfer its energy immedietly upon impact than a sleek pointed projectile when bullet construction of both designs is equal.
The differences become even more pronounced when using solid, non expanding bullets, whether they be constructed of hard cast lead or full metal (copper) jackets. Unfortunately, a wide flat pointed meplat can also handicapp a projectiles potential trajectory as well as a huge loss in velocity and energy at moderate to longer ranges which can inturn result in low energy transfer.
Ideally, to fully utilise a wide, flat meplat projectile, it needs to be used in firearms that are designed for close range work or- in cartridges which already have such low velocity, that trajectory is not greatly effected by bullet meplat design.
Historically, U.S Gun writer Elmer Keith was the first hunter to both study and publish the effects of a wide, flat meplat, non expanding projectile used on game. There were definitely other hunters and ballisticians experimenting before him but it was Keith and his tenacious nature that made the wide, flat meplat into a 20th century issue. Keith pioneered the design of a flat point 250 grain .44 calibre hard cast lead pojectile for his .44 special revolver in 1926 with results that would forever shape his opinions on hunting bullet design and forever influence his staunchest fans. Yet today, more than 80 years later, the subject of metplat shape and surface area is largely untapped
Mechanisms
In plain terms, a wide flat pointed solid non expanding bullet, even if driven at handgun velocities, creates disprortionate to calibre wounding where a pointed, non expanding bullet would create a calibre sized wound. It is this dis-proportinate to calibre wounding that is of most interest to the hunter as it is this mechanism that promotes fast clean killing.
The physics involved in wide/ flat meplat wounding are very simple, the flat point meets huge resistance on impact causing the water in flesh to be forced violently away from the path of the bullet, this in turn results in broad wounding. At velocities above 1700fps and using a wide calibre, the .45-70 (.458") which this article is focused around, entry wounds using the widest possible meplat may be up to an inch in diameter with the wound channel slightly larger and remaining the same diameter for several feet. This opens up both the possibility of both broad wounding with solid projectiles combined with penetration not normally available with expanding type projectiles.
At this point it must be noted that, the higher the impact velocity, the greater the resistance. This occurs simply because the water molecules of the animal, cannot move away from the flat point bullet at relative speeds. So as velocity is increased, wound channels increase in diameter however penetration may not necessarily be deeper due to increased resistance at the target. Pointed FMJ projectiles do not seem to show much difference in wounding or penetration at varied velocities. As an example, a 147 grain 7.62 FMJ projectile fired from a .300 Win mag creates the same size permanent wound cavity as it does when fired from a .308 Win rifle. Some extra bruising does occur throughout the lungs however the actual speed of killing remains unchanged and kills with this projectile on medium game are generally slow.
Oddly, although entry wounds with wide flat meplat bullets are almost always large, non expanding bullets of this style do not seem to produce hydrostatic shock at the typically low muzzle velocities produced by big bore rifle and handgun cartridges. By hydrostatic shock, I mean the ability of the projectile to send a shock wave through the ribs and into the spine with such speed that the central nervous system shuts down the brain (temporary coma) during which time the vitals bleed out before the animal regains conciousness, giving the illusion that it has died 'instantly'.
Due to the fact that slow, non expanding wide, flat meplat projectiles do not produce any shock effect whatsoever, when using such bullets on dangerous game, hunters are advised to expect clean but delayed kills, a potentially deadly situation. Flat meplat non expanding bullets definitely give optimum results when striking major bones. When bones are hit, wound channels change from being consistant 1 to 2" wide wound channels to much more dramatic wounding. When this type of bullet strikes bone, the fragments that separate tend to be very large and incapacitating.
On average, again using the .45-70, wound channels created by flat meplat non expanding projectiles are about four times the size of the original .458" calibre hard cast bullet however expanding projectiles in .45-70 will normally produce internal wounds twelve times their original bullet diameter at close ranges and in high velocity loadings. Needless to say, expanding bullets are capable of producing faster kills. The use of a flat meplat non expanding bullet therfore requires careful consideration.
As stated, wide, flat meplat non expanding projectiles are typically slow or 'delayed' killers, even with good shot placement. This can pose serious problems when hunting large dangerous game. Worse still, in a moment of intense stress such as during a charge, poor shot placement by the hunter may lead to minimal wounding where a premium controlled expanding bullet may have been capable of more devastating wounds. It is a tough call, on frontal shots, the flat meplat non expanding projectile driven at moderate velocities, even if missing the vitals or forwards locomotive muscles and bones, still has the potential to smash pelvis and rear leg bones. Several reports indicate that hunters have indeed anchored large heavy animals in this way.
There is not only great room for experimentation with wide meplat bullets, but also expanding wide meplat bullets, an area which most manufacturers have yet to tap into. Authorities on the subject of wide meplats generally view .300" as being the minimum and .360" being the maximum practical width for meplats of .458" calibre. These measurements prove true when tested on game and the difference that an .060" (1.5mm) increase in meplat width makes to wounding and fast killing is often dramatic.
Below are a series of photos taken from a simple days experimentation with the .45-70. The game hunted on this occasion were simply feral billy goats due to the fact that it allowed me to repeat tests over and over in a semi controlled environment- close range bush hunting where the abundance of game allowed me to take identical shots throughout a series of gullies. Average body weights for these animals was 50kg (110lb) and all animals were shot when relaxed, none were adrenalised before the shot.
The projectile used in the experiment was the Speer 400 grain flat soft point, a very good allrounder for a huge variety of game including light/ lean game up to bodyweights of around 320kg (700lb). What made this experiment interesting is that animals were taken with the Speer bullet fired backwards as well as forwards. Kids, don't try this at home. While the Speer is one of the few projectiles which already offers a generously wide/ flat meplat, firing it backwards offered the maximum width meplat possible for the .45-70. The rifle (a custom bolt action) was also tested for accuracy and surprisingly, the backwards Speer grouped well and showed no signs of instabilty when observing the uniformity of bullet holes through paper.
The purpose of these experiments was really to determine speed of killing. In recent years there has been a lot of argument throught various public hunting forums as to the effectiveness of a wide flat meplat bullet travelling at low velocity for use on dangerous game in comparison to both a low velocity expanding projectile and at the other extreme, high velocity big bores such as the .460 Weatherby. Each of these has its strengths and weaknesses. The most important factor is that the hunter be provided with correct information as to what to expect when each load is used on game and how to utilise projectiles, exploiting the strengths of the projectile designs.
For my own part, I much prefer the extremes, using a high velocity big bore. I am not so much a fan of clean but slow kills, regardless of deep penetration. I have used the .45-70 and the 400 grain Speer to take wild cattle but much prefer something a whole bunch faster. High velocity and careful shot placement gives me great satisfaction but I am also aware that penetration may be sacrificed on angling shots. For others, a classic big bore cartridge from yester year is far more thrilling to use than my latest ten million magnum. Variety is certainly the spice of life.
As for wide, flat meplats in small bores, the greatest problem with wide meplats in the small bores is that ballistic co-efficients are greatly reduced, especially with regard to wind drift. Such changes tend to handicapp otherwise flat shooting cartridges with the negatives outweighing any other benefits. Secondly, most small bores have high velocity in their favor, a major proponant in wide wound channel creation negating any need for increased performance. Perhaps the only advantage of using wide meplat non expanding projectiles in high velocity small bores would be in the design of full metal jacket projectiles in 7mm and .30 calibre for follow up shots on large game. In military ammunition, a small flat point rather than a fully pointed FMJ jacket does make a notable difference in stopping power, the ramifications are obvious.
Some examples of flat meplats disscussed throughout the small bore texts of the book Hunting cartridges of the World include- the Norma Vulcan in 6.5mm, 7mm and .30 calibre along with several brands of flat point .30-30 bullets. Of these, the Vulcan in all calibres and the .30-30 Sierra projectiles showed very good results.
Wide meplats really start to become more and more useful in the .358" calibre and upwards. Many medium bores are utilised at limited ranges of up to 200 to 250 yards and in such cases, the poor BC's created by wide meplats is of little handicap. By simply changing from a pointed soft point to a round nose soft point, many cartridges become fast killers on light or lean game where before the bullet may have carried too much momentum, failing to impart its energy. Results of the change in bullet style in the medium bores are often dramatic on all manner of game. That said, only a very few, mostly custom bullet makers, offer true flat point medium bore projectiles. Most manufacturers offer round nose bullets, nevertheless, the Woodleigh Welcore, mentioned throughout the medium bore texts, is a good example of a fast killing round nose bullet in comparison to its pointed counterpart. Both of the Woodleigh designs have their strengths which are explained in the medium and big bore texts.
As discussed, Elmer Keith was one of the very few hunter/ researchers that experimented with wide meplats in large calibres. Keith's work revolved around experiments in the calibres .38 (.357"), .44 (.430") and .45 (.451") with non expanding bullets. Very few others have experimented with big bore wide meplats, most notably Garret Cartridges inc, experimenting with both .430" and .458" calibre bullets while Lyman, Lee and RCBS offer Keith style bullet moulds. Speer are the only manufacturer to offer a wide meplat jacketed soft point bullet which comes in the form of the .45-70 400 grain jacketed flat point. Apart from this, the market remains open to the development of wide, flat meplat expanding soft nose bullets.
For those who wish to use a hard cast, non expanding, wide meplat big bore bullet for hunting large, heavy bodied dangerous game, shot placement is the key to optimum results. The hunter must attempt to destroy the autonomus plexus of game if possible, with the first shot. For many hunters, this is not a natural point of aim. The autonomus plexus is located at the junction of the heart and lungs in all mammals and viewed broad side, it is located at the ball joint intersection of the scapula and humerus bones. This joint is slightly forwards of the line of the front leg. That said, this point of aim is only applicable for broadside shots. Front on, the autonomus plexus is located at the center of the chest but slightly high, from quartering angles, the hunter must be able to visualize the autonomus plexus and aim shots accordingly. For newer hunters, performing these mental checks in the field can end up overwhelming, resulting in a generalized chest shot. The only way to avoid this, prior to a big game hunt, is to practice over and over, either mentally (visualization) or when hunting lesser game or even on small game, using a .22lr.
More information on game anatomy and killing can be found within the TBR knowledge base game killing text.
In the photo below, I have shot a dog tucker Angus cattle beast with the intention of breaking the front leg and destroying the autonomus plexus however I missed my point of aim by quite a margin. Point A is where my bullet hit versus B, the intersection of the humerus and scapula. I am holding the leg at an angle to show that the humerus bone is broken.
Below, the same beast, cut open, showing the layout of the vital organs (while a smear of beef fat on the camera lens has pretty much ruined any chance of clearer photos). The animal was slightly quartering on to me, the bullet struck the foreleg, passed through point A (top of the heart) and exited just behind the off shoulder. Point B shows the location of the autonomus plexus relative to the angle I was shooting from. Very little wounding can be seen due to the bullet style I used, a prototype GS Custom homogenous copper pointed bullet in a .375 RUM which after expansion, was somewhat similar to a hard cast wide meplat bullet. This bullet style combined with my shot placement, make it appear as though only a small degree of wounding has occured. Nevertheless, the top of the heart was severed along with good wounding through the offside lung. Death occurred in a matter of seconds. The rifle in question was built by NZ gunsmith Arthur Cleland and is a very accurate rifle.
Disclaimer/ WARNING: The views and opinions expressed in this article are solely those of the author and are not endorsed by any manufacturers. Terminal Ballistics Research and the author take no responsibility for the use or misuse of any views, opinions or information expressed in this article.
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