i have been writing of "jj's brit" ™ in the context of long range shooting.
in the past several weeks the little cartridge has been shot at various ranges to calibrate the cartridge's trajectory and accuracy, e.g., to hit a given target for example at 400 yards with the scope set to the range of 400 yards. as a practical matter, given the limitations of the scope which is a 2.5-8x36mm scope and the amount of the target subtended by the intersection of the cross hairs, the cartridge in my rifle with my scope begins to have failing utility at 600 yards, while by contrast it very readily hits where aimed at 500 yards.
the problem is simple. at 600 yards, the intersection of the cross hair obscures the target circle i am aiming at, which is a 9" circle. while, at 500 yards, the scope magnifies the target sufficiently that i can place the intersection of the cross hairs on the 9" circle with precision.
so, as i have noted, for me, and for shooting targets at 600 yards, with this scope and this cartridge, the rifle, scope and cartridge combination is of declining utility much beyond 600 yards.
now, given all of the above, does this mean that "jj's brit" ™ cannot be an 800 yard battlefield rifle?
no, it does not.
for instance, were a high power scope with greater resolution mounted, and a greater image size in relation to the cross hairs available, that would then allow the rifle to be aimed more precisely at longer ranges. and, i think the cartridge inherently accurate enough to take advantage of better optics.
or, consider the effect of making the target larger. at my range, we have a metal gong set up at the 300 yard target standard. it is a 14x18" rectangle. hitting it w/ "jj's brit" ™ at 300 yard w/ my rifle and the 2.5-8x36mm leupold scope is like dropping a wad of paper into a garbage can: the reticule is simply surrounded by target. were the 14x18" rectangle moved out to 800 yards or so, than even with the 2.5-8x36mm scope, i would be able to calibrate the scope settings, and see enough of the target to aim accurately, and strike the target with regularity at that distance. of that, i am fully confident.
i have friends that have scopes that go to 14 to 18 power, some above 20 levels of magnification. with an accurate rifle, and a steady rest, to hit targets at great distance is not difficult if the scope, cartridge and rifle combination are calibrated to do so. and, if the cartridge will shoot into a minute or a minute and a half, which the little "jj's brit" ™ will do quite easily.
the american and british military, and others i presume, have been shooting at great distances for years, and did so before the advent of the modern high magnification rifle scope. even so, they hit the targets they shoot at with regularity, and with sufficient precision that their efforts are "scored." (i read of a british military rifle competition using enfields and the .303 british shot at 1,000 yards, in which it was determined that the bullets on their way to the targets were elevated in mid trajectory at over 30' above the line of sight. not 30", but, 30". that's pretty extraordinary.)
they shoot at very large targets.
in national rifle association sanctioned matches, the standard "x" ring dimension is a 6" diameter circle, at 600 yards. the standard 10-ring is 12" in diameter: the inner circle is used to break ties, if competitors have the same score, the one with the higher number of x's wins. the standard 9-ring at that distance is 18" in diameter. the 8-ring is 24" in diameter, and the 7-ring is 36" in diameter.
likewise, in n.r.a. sanctioned matches, at 800 yards the stand "x" ring dimension is a 10" circle, the 10-ring is 20". the 9-ring is 30", and the 8-ring is 44" in diameter. the 7-ring is 60", nearly the height of a full grown soldier.
now, if you could hit the x-ring at those distances with regularity, you would have a chance of hitting a target the size of a human head, and you would be a skilled rifleman, indeed. and, as a matter of fact, shooters do hit the "x" ring at those distances, even though they cannot see it, as a practical matter: it is pretty small though an aperture sight. (the solution? the entire "bulls eye" is "sat on top of the front sight post," the shooter having determined the settings necessary to elevate the bullet into the middle of the image he can see. does that make sense? well, it's what they do. in shooting, it is not so much seeing what you see, but understanding what you see. and, the implications of that. is that all clear?)
but, notice something. the military, and its civilian adjuncts in target shooting, consider the ability to hit a 60" circle at 1000 yards worthy of receiving points. it is only when you cannot place a bullet within a 72x72" square at 1000 yards that you do not earn points for your shooting. you cannot hit a 6x6' square, you don't get any points. it is a "miss."
likewise, the 5-ring at 600 yards scores the lowest, and it is 60" in diameter. if you cannot get the round into that circle, then you score no points for that shot.
what gives? why am i not satisfied with being able to put a bullet into a 9" circle at 600 yards, while the military and the n.r.a. will give you some points if you can hit a 60" circle?
well, it is simply a matter of goals and standards for me, and for the military, it is simply the matter of whether a particular rifle shot has a discernible utility at a given range. i want to shoot as accurately as possible to be able to evaluate the cartridge i am developing with a critical eye.
the military is trying to measure and predict a soldier's ability to kill or wound an adversary at a given distance. or, more precisely, the military is trying to predict the number of times a group of soldiers trained to a common level of proficiency will hit multiple targets firing a given number of shots.
and, the miltary is not particularly concerned whether the combination of a soldiers shooting skills, and the accuracy of his cartridge, rifle and aiming system can hit an adversary with every single shot. it is simple. in the military, if you don't hit the fellow on the first shot, you don't quit in disappointment, you simply shoot again, and again, and until you've either hit what you are shooting at, or you have sufficiently dissauded you adversary that he quits the field, surrendering it to you.
and, if you don't hit your opponent, and kill or wound him today, then there is always tomorrow, most likely. unless of course, he hits you, either killing or wounding you.
the fact is this. if you can put a bullet into a 60" circle at 1000 yards, it is not necessarily a miss or a wasted effort, ... , statistically speaking, it is quite likely to disperse into a given area: in other words, it is just as likely to hit someplace as anywhere else, within a defined circle. (that is a bit crude, and distribution curves and the like govern the real analysis. but, as a metaphor, it is workable. you drop a golf ball into the bottom of a bucket, it hits something. and, sometimes, just what you are aiming for.) if you convert that into shooting at someone inside a circle that you are proficient at hitting, that means you may miss him entirely, or you may shoot him right in the kisser. and, the odds of hitting the soldier right in the kisser increase with every shot, though by saying that, i know that i make every statistician on earth cringe in disgust and horror. hey, my attitude is that is why they sell a lot of lotto tickets, so get used to it, pencil pushers.
on the other hand, you drop a point in a contested rifle match, you may lose the match on that dropped shot. and, if you are striving for mechanical predictability and regularity, the inability to place shots with precision is disturbing.
so, what is a 6 or an 800 rifle? well, it all depends on your goals and objective.
now, i was recently reading a "chat room" where the members were debating whether a given cartridge was a suitable military round at 800 yards. some scoffed, as if the cartridge could not hurl a projectile that far, which is utter nonsense, and others said, heck, i can hit a target that distance very easily with that cartridge, and i've done it.
in no wise were the factors above discussed.
what is the target for a miltary round at 800 yards? is it an 8 inch circle, or is it a 60 inch circle? and, from a military view point, when are the number of hits in relation to the number of shots taken sufficient to justify the use of a round at that distance? and, again, this has a pretty fair relation to the issue, what is the target, and how big is it?
and, finally, the issue boils down to, what is the round's lethality if the shooter actually hits something with it? now, for a target shooter, the lethality of a round at distance is the number of points he can score on a target with it, at that distance. for a soldier, the question devolves around the issue of whether he kills, or disables, or so frightens an adversary that he drives him from the fight, and causes him to give up the ground which is contested. and, as an added matter, there is the consideration of whether the discharge of a weapon is reassuring to the person wielding it, or whether he feels frustrated because of a perception that the round is inadequate to kill or disable his enemy.
so, to evaluate a rifle cartridge, rifle and aiming device combination, you have to define what your reasonable performance expectations are from the shooter wielding that weapon, and from the weapon itself.
now, the other day, when i was shooting at the 9" circle, i was not satisfied with the fact that 4 of my shots landed on it, but in a dispersed fashion, and that 2 shots were near misses, probably within 3 inches or so from the outside of the target.
that's target shooting.
but, say that i was in an armed conflict, and that 9" circle were in the center of an unarmored enemy soldier's chest, or multiple chests, and i would have been quite pleased, indeed, for my little "jj's brit" ™ packs sufficient punch to be lethal at that distance.
but, say that i were a military sniper, whose job was to take out high value enemy personnel as targets, i would not be satisfied with that, because of the fact that the probability of a killing shot, every time, gets slim with that kind of accuracy. and, if you cannot hit your target with a fair degree of predictability first shot out of a cold barrel you chances of being detected with multiple shots to get the job done, go way up. and, snipers do not consider themselves to be on suicide missions. they want to get away, and fight another day.
so, whether any weapon and its cartridge are adequate to a task is entirely dependent upon how the task is defined. and, any discussion of a weapon's suitability is just jaw flapping unless the task is clearly and precisely set out.
so, my little "jj's brit" ™ is not up to snuff by my lights, not just yet, because the relatively low magnification of the scope does not allow the level of precision in aiming at a 9" target that i want. i want to be able to place a shot from a cold barrel into a 9" target at 600 yards, every time.
this is a trouble with the weapons system, and not with the cartridge.
so, my little "jj's brit" ™ is a fully adequate cartridge, in my estimation, for military usage on the 800 yard battlefield, by the average infantryman with average to adequate shooting skills, and in the hands of a skilled shooter would be very lethal, indeed. that military shooter is not looking for a one shoot kill of an adversary with every shot, if he is your average infantryman. he is, however, looking for a weapon that is sufficiently lethal and/or destructive if he does hit his target, and that will give him a high probability of being able to hit his target if the weapon is properly and skillfully aimed. in that case, any cartridge which is effective against a small deer, is likely to be effective against your average small infantryman. and, "jj's brit" ™ fill the bill, quite nicely, thank you.
you have to know what you want.
you have to know what will satisfy your needs.
john jay @ 09.25.2012
p.s. i can think of no source better able to tell us what an accurate cartridge is, given its defined purpose, than the united states military. the military is, after all, engaged in marksmanship training, in target shooting, in sniping and in rifles and cartridges which set the acceptable standards for combat usage.
in the 10th edition of "cartridges of the world," by frank c. barnes and edited by stan skinner, krause publications, iola, wisconsin, 2003 we find chapter 17, pages 487 to 503 which sets forth the technical specifications for military small arms ammunition.
let's look at the 7.62x51mm nato, commonly known as the .308 winchester in its civilian guise. i choose that cartridge because it is, indisputably, an 800 yard cartridge. so, it ought to be interesting, in terms of the above discussion, to quantify what the military thinks is adequate accuracy for a given cartridge, filling a specific performance niche.
all of these entries, though they use different "model" designations pertain to the 7.62x51 nato cartridge.
the target round.
cartridge, 7.62mm, match, m 852
weapon: rifle, 7.62mm, m 14 (national match)
velocity: 2550 +/- fps at 78 feet
pressure: 50,000 psi, max average
accuracy: 3.5" mean radius, max. avg. at 600 yards
cartridge: 383 grains, app. [total weight: jjj]
case: 190 grains
bullet: 168 grains, hollow point boat-tail [generally speaking, the 168 grain sierra]
brand: imr 4895
type: single base, tubular
weight [of powder charge]: 42 grains
ident.: ..... nm stamped on head of case of cartridges for national matches
the general utility, e.g., combat round.
cartridge, 7.62 nato, ball, m 80.
weapon: gun, machine, 7.62 m60; m73 rifle, 7.62mm, m 14
velocity: 2750 +/- 30 fps at 78 feet
pressure: 50,000 psi, max. avg.
accuracy: carton or clip pack -- 5" mean radius, max. avg. at 600 yards
link pack -- 7.52" mean radius, max. avg. at 600 yards
cartridge: 392 grains
case: 190 grains
bullet: 149 -3 grains
type: double base single base single base
spheroidal tubular tubular
weight: 46 grains 41.5 grains 41 grains
identification: plain tip
there you have it.--
the military considers a cartridge of suitable accuracy for combat if it will shoot into a 10" circle at 600 yards. now, i am not a statistician, but i know the term "mean radius" as used in the above standard implies a recognition of the part of the military that some rounds are going to land outside that 10" circle, just because of statistical variation. because some do, does not mean that the rest do not meet the specified criteria on a statistical analysis.
you may rest assured, that the army considers the 7.62 nato an 800 yard battlefield cartridge. you may also rest assured that some idiot is not going to be jumping up and down at 801 yards distance from a soldier armed with the 7.62x51mm nato, because he feels "statistically impervious."
the military also feels that for its target shooting, which is done using iron/open sights, and not optical sights, that a mean radius of 3.5" at 600 yards, or a 7.00" circular, to be quite suitable for its purposes.
remember the discussion above, with regard to the size of the military target at 600 yards. while the x ring is a very small 6", (it's not very big even with a scope sight, and i doubt you "see" it as a distinguishable dimension with just your eyes), the 10-ring is a full 12" in diameter, and the 8-ring is a full 24" in diameter. to put the matter succinctly, you can score points on a military shoot if you can put a bullet within a 24" circle. (remember, as a matter of statistical analysis, one of many shots landing in a 24" circle is just as likely to hit it tending toward the middle, as it is likely to hit it tending toward the periphery. thus, sooner or later, the guy hitting the circle, is going to hit someones head lying in the middle of it. all it takes is time and ammunition. the military has plenty of both. mission accomplished.) (the secret of course, is to prevent the operation of this truth from happening to you.) (this is true in the gross, and the finite situation.)
which, i might add, is not that damned easy using the protocols in high powered rifle shooting, and the positions, time constraints and other factors involved. the point is, it is well within the capability of 7.62x51mm nato ammo, target or combat, if the shooter can aim his weapon precisely.
and, once again, we are right back to the nub of the issue, and that is the definition of utility that is being used to evaluate shooter, rifle and cartridge performance at long range which defines the outcome of the discussion.
the military is in the business of combat operations which kill a large number of people over a given time frame, and they are not so much interested in the outcome of each individual shot, whether for tactical, strategic, aesthetic, competition and evaluation of personal skill, as they are in the gross numbers involved.
the military kills by the gross.
the target shooter shoots for points, and dropping a point can cost a match.
the sniper kills to protect his fellow soldiers, and to preserve his escape from a crowded environ.
an old duffer, who contemplates civil affray and who has concluded over a life time of reading and study that battle is dangerous and that people can get seriously killed participating in it, probably is looking at the matter with the finicky attitude of the sniper, unless i miss my guess.
to that latter person, it is highly desirable that he be able to hit an 8" circle at 600 yards, the first time, every time out of a cold barrel. he who limps away, lives to limp & fight another day. accurate shooting is very important to safe limping. jjjay.