correction: the wonderful thing about blogging is one gets to display ones shortcomings and stupidity in full view of the reader. in several places below i have referred to the 5.56x45mm nato as the "5.56x41mm nato." dumb. oh, well, even though i have confessed to being a dolt, you may still regard all other representations and opinions expressed herein-below as authoritative. oh, well, i guess i'll live through the embarrassment. my apologies, nonetheless. end correction, lamentations and breast beating.
the american antelope, known colloquially as the "pronghorn," is a small antelope (technically, pretty similar to a goat, actually, "pretty much" a goat) in which the male grow to 150 lbs or so, a big specimen perhaps weighing a bit more. they have a small horn which is shed annually (please don't explain to me the difference between horns, usually not shed, and comprised of fancy hair, and antlers, which are bone, and are shed annually ... the pronghorn is what it is), and is not particularly for defensive use. the animal relies on great eyesight (seeing about 320-degrees of arc from large eyes at the top of the skull) and blazing speed which it sustains for long duration. i believe a pronghorn would leave your average cheetah pretty well spent and frustrated, and still hungary: they are quite capable of running perhaps as much as 70 mph for a long ways. http://en.wikipedia.org/wiki/Pronghorn . any kind of a head start, and the cheetah is dining on dust.
they are hunted rather avidly in the united states, and a large male is prized.
but, this is about the 6.8mm remington spc cartridge.
in the january 2012 issue of "guns & ammo," (volume 56, no. 1), at page 30 author dick metcalf has penned "hunting hotshot: the 6.8mm spc" in which he recounts a successful hunting trip to bag an antelope, considered "resident" by the state of wyoming.
i am not going to recount various sundry details of the article, except i will excerpt portions of the article relevant to the ballistic performance of the 6.8mm rem spc upon a pretty tough little game animal: they aren't very big, but they require a well placed shot to put down quickly.
after some general remarks, metcalf describes a new load from hornady developed specifically for hunting large game, of the smaller variety:
"the hornady load features the company's proven sst hunting bullet in a new 120-grain weight. its .400 bc gives it remarkable downrange energy retention and ballistic stability. it is also the heaviest bullet currently loaded in any commercial 6.8mm spc round from any manufacturer. hornady's catalog specs call for a muzzle velocity of 2,460 fps and 1,612 ft-lbs energy from a 16-inch barrel. from my stag arms 16.5-inch barrel, the actual velocity reading was 2,534 fps (1,711 ft-lbs [muzzle energy]). retained energy at 300 yards is still 1,000 ft-lbs (more than a .44 magnum revolver at the muzzle), and the drop at 300 yard with a 200-yard zero is 10.5 inches." page 32.
brits with a memory will instantly recognize the similarity of the 6.8mm remington spc to the ill-fated .277/.280 british infantry round developed by the british military looking for a cartridge to replace the .303 british after wwii. http://en.wikipedia.org/wiki/.280_British . i think the .280 british the finest intermediate infantry cartridge ever developed, and quite superior to most such rounds ever adopted, including the 7.62x39mm (model 43) used in the ubiquitous ak-47 and sks rifles developed by the russians. unfortunately, the united states military did not, and its insistence upon adopting the 7.62x51mm as a nato standard after wwii led to the .277/.280 brit and the em-2 assault rifle being shunted aside. http://en.wikipedia.org/wiki/.280_British . oh, well.
but, you will note that the 6.8mm rem spc is pretty much a warmed over .280 brit, getting similar ballistics from a little smaller case because of better performing powder than available to the british military in the early 1950's. the .280 brit, however you look at it, was capable of shooting a little heavier bullet to somewhat higher velocities, and it too had very good ranging characteristics. and, those are facts, jack. quite. irrefutable.
but, back to author metcalf's concluding remarks on his hunt, and the performance of the 6.8mm remington spc. says he:
"i zeroed my carbine at 100 yards, punched in the right numbers and tested it in wyoming on a softball-size rock from a sitting position at 316 yards. [no self respecting gun "journalist" goes anywhere without a laser range finder, provided gratis by some manufacturer or another]. whacked it three times in a row. when a pronghorn buck stepped out at 205 yards, i put the aiming dot on hte point of his lead shoulder and hit the point of aim exactly. the 120-grain hornady sst shattered the shoulder bones, took out his heart and lungs and exited behind the last rib on the opposite side. clean kill.
"what more could you ask for." page 32.
you are going to have to take my word for it, but the north american prong-horned antelope, though small, is a very tough little critter, and possessed of unusually strong bones in the legs, and presumably in the shoulders.
the "evidence" of the 6.8mm's ballistic properties in this article are entirely anecdotal. but, even so, they suggest to me that the 6.8mm remington spc is entirely capable of handing almost any sort of 150 to 250 lb mammalian that it might encounter. if the bullet in the hornady cartridge used to hunt the animal in this story could take out a shoulder with a point on hit, and then heavily damage the heart and lungs as depicted, and then exit the animal, then the cartridge may be considered formidable to the average human, indeed. i would venture the bald faced opinion that an american prong horned antelope is as tough as, or a good deal tougher, than any two legged opposition to be ever encountered, anywhere.
and, though metcalf is partisan to the 6.8mm rem spc, having stated in other sources that if limited to one rifle (what a ridiculous concept) it would be in this cartridge, you may rest assured that he is regarded as being a straight forward and fact based reporter. he is not one to misstate a situation or an observation, and is very well respected among outdoor/gun writers.
that's the simple truth.
i think that from this and other reports you may consider the 6.8mm remington spc as ample for the bottom end of big game, and more than ample as a defensive weapon against human depredations. i shoot my 5.56x41mm nato at the same 300 steel gong that i shoot my 6.8mm remington spc, and the 6.8mm gives an authoritatively greater whack when it strikes steel. it is way more cartridge than the 5.56 nato, and it is way more cartridge than the 7.62x39mm (model 43) russian.
it is capable of hunting game, and it is capable of defending nation, kith, kin, hearth and home.
john jay @ 12.14.2011
p.s. conciliatory note to you brits who may be reading.-- the 6.8mm remington spc though a fine intermediate cartridge is not the cartridge that either the .277 brit or the .280 brit was, in any of their permutations, and had either or both of those cartridges been adopted in the early 1950's there would have been no need for the 6.8mm remington spc now, nor the 5.56x41mm nato, for that matter.
the .280 brit was just a superior cartridge, even better than the italian 7.35 terni. you think that a silly thing to say?-- look at the case dimensions of the italian terni, and the 7.62x39mm russian (model 43), and you will understand what i am saying, and you will also understand that the russians researched the terni very thoroughly.
there really isn't anything entirely new in ballistics. look around a corner, and you will see the departing shadow of him who has been there before you. and, that's a fact, jack.
p.s.s. if great britain went back to the drawing boards, resurrected either the .277 or .280 brit as originally developed, and then readopted a scaled down fn fal for a battle rifle, they would once again be in possession of the world's finest intermediate cartridge, and one of the world's great rifles. still. the cartridge was that good, and so was the fn fal. facts.
i wouldn't lament the passing of the em-2 that much.
an index of posts on the 6.8mm remington spc cartridge, including notes on hand loading issues, and the development of a good hand load. -- http://wintersoldier2008.typepad.com/summer_patriot_winter_sol/2010/07/an-index-of-posts-on-the-68-remington-spc-adventures-in-reloading-making-the-ar15-work-in-this-chamb.html .
