Inherent Accuracy
Question:
: The empirical data produced by target shooters has shown that the 308 is : an inherently accurate cartridge – and that’s why most of them who shoot : full bore (high power) use 308. The same is true of some other : cartridges, such as the 222 Rem: it is inherently more accurate that the : 223 (whch is slightly longer). But note that the 22PPC is held to be : more accurate than the 222, which is why is replaced the 222 as the : cartridge of choice for bench-rest shooting. Note also that the PPC : cartridges are short and fat. The PPCs probably have an edge that goes beyond just having a short, fat powder collumn. There are many BR cartridges which are very similar in case capacity to the 6 PPC (6mm Waldog, 6mm Talldog, 6mm Remington Bench Rest – or 6BR). 6PPCs remain popular though losses to various 6mm wildcats of similar proportions have and continue to occur. Some argue though that the edge achieved by the PPCs is due to it’s more narrow flash hole compared to other similar designes built around a standard .473" case head (.308 style). The effect of the primer on the powder column and it’s subsequent disruption is another argument for "short-fat" versus "long-thin" as far as accuracy is concerned. One trait that all "inherently accurate" cartridges posses is that they are efficient. The more overbore a cartridge, the less efficient it becomes, the harder it is to find top performing, accurate loads. The .308 is one of the most efficient of the .30 caliber cartriges. From a hunting perspective efficiency can be important because it can allow you to have all the power you need in a rifle that is short, has minimal recoil, and is light weight. Some talk recently has been made of the Browning BLR. Chambered in .308 this rifle becomes one of the most accurate, handiest rifles around capable of reasonable shots on any north american game animal (with the proper load). In performance it is just barely behind a 30-06 for all but the most heaviest bullets yet it is quite a handy little rifle. In contrast, the .22-378 (no that’s not a typo) represents pehaps the epitomy of inefficiency. Sure you can get a 40 gr. ballistic tip to over 5000 fps but in general the price is heavy. With an expected barrel life of around 100 rounds or so it’s doubtful you could get far enough along to develop accuracy loads. Regards, Rick Visit the rec.hunting and rec.hunting.dogs FAQ Home Page at: http://sportsmansweb.com/hunting/
Response:
- Hide quoted text — Show quoted text ->Jonathan, what is the scientific basis for making a claim that a certain >cartridge is more inherently accurate than another? > It’s not a scientific basis, so much as empirical from which the > following hypothetical conclusion is drawn: cases that are short and fat > are more accurate than long thin cases, and this is because they result > in more uniform burning of the powder. >I’m wondering what your reasoning is. (I’ll >post this also to the group so all might benefit.) > I’ve debated this point (that cartridge A is ‘inherently’ more accurate > than cartridge B) many times, and been persuaded to this line of > thinking. In this debate, we make the presumption that the rifle under > test is of the finest quality (i.e. a custom target rifle) and *not* a > randomly selected factory made rifle. > The empirical data produced by target shooters has shown that the 308 is > an inherently accurate cartridge – and that’s why most of them who shoot > full bore (high power) use 308. The same is true of some other > cartridges, such as the 222 Rem: it is inherently more accurate that the > 223 (whch is slightly longer). But note that the 22PPC is held to be > more accurate than the 222, which is why is replaced the 222 as the > cartridge of choice for bench-rest shooting. Note also that the PPC > cartridges are short and fat. > The 6.5 Swede is an oddity, according to the above theory, since it has > a reputation for accuracy but cannot be described as short and fat. > However, ‘accuracy’ can be a relative thing and since the Swede is > mainly used as a hunting cartridge, maybe that indicates what is meant. > I have no personal experience of the Swede, but I note that in this > country and in the USA it isn’t in the forefront of target shooting. > Maybe our Scandanavian friends can comment?
You observations can be supported by the fact (re .308) that most competition shooters once used 30-06 and then it was discovered that newcomers with less experience were beating the best of them using .308 in similar weapons. Given it was becoming almost impossible for someone to win using 30-06 no matter what they did to the rifles, today, almost everyone uses it in such competitions. Now, how important is it to hunting in the real world? About as important as being able to shoot something between the eyes rather than hitting it in an eye. Simple translation, same amount of meat on the table whichever gun a good shooter uses. Probably important to police snipers and competition shooters only. Visit the rec.hunting and rec.hunting.dogs FAQ Home Page at: http://sportsmansweb.com/hunting/
Response:
>Jonathan, what is the scientific basis for making a claim that a certain >cartridge is more inherently accurate than another? I’ve heard this >before in regard to the .308 family of cartridges, and also the 6.5 x 55 >Swedish. You mentioned this obliquely in a recent post and, since I >respect your objectivity, I’m wondering what your reasoning is. (I’ll >post this also to the group so all might benefit.)
The reason most given for 308 Win being more accurate than, say, 3006 is the short powder column. For the Swede, its long-for-caliber bullets. I don’t know for sure that either is true. Frankly, I think that if the amount of energy that’s gone into load development for the 308 Win was put into just about any other cartridge, you would get similar results. The real factors in accuracy are in the launching platform. Just my *humble* opinion. ..P Visit the rec.hunting and rec.hunting.dogs FAQ Home Page at: http://sportsmansweb.com/hunting/
Response:
Uh oh, I smell a fire smoldering! Visit the rec.hunting and rec.hunting.dogs FAQ Home Page at: http://sportsmansweb.com/hunting/
Response:
> The 6.5 Swede is an oddity, according to the above theory, since it has > a reputation for accuracy but cannot be described as short and fat. > However, ‘accuracy’ can be a relative thing and since the Swede is > mainly used as a hunting cartridge, maybe that indicates what is meant. > I have no personal experience of the Swede, but I note that in this > country and in the USA it isn’t in the forefront of target shooting. > Maybe our Scandanavian friends can comment?
Mr Spencer, Your assessment of the .308 (or "fat") family is accurate, there is more to the 6.5×55 story though, I’m sure. Its also a very popular target cartridge there, maybe the most popular in Scandinavia. I’m sure the Swede’s accuracy can be attributed to a lot of things. First, I think the M96 is a very well made weapon, and is possibly the basis for some inexpensive custom sporterizing there. Also, its a lightly recoiling rifle, we know how severe recoil can affect a shooter’s ability to hold in the black. Another possible reason, one I think has the most significance, is the long bearing surfaces and great sectional density in heavier bullets in this cartridge. This contributes I’m sure to the bullet’s ballistic coefficient downrange. The 6.5mm bullet, when launched at even mild velocities, bucks the wind better and is probably more gyroscopically stable than .284 and .308 bullets of equal weight. The only (maybe I mean cheapest) way to improve the latter two is to increase velocity, which of course has a recoil tradeoff. Just a thought. (Yup, I’m a big-time fan…) Dave Manfred and Remy (GSPs), Mauser (GSD) http://www.geocities.com/yosemite/rapids/7061 A Prince, whose Character is thus marked by every act which may define a Tyrant, is unfit to be the Ruler of a free People. Decl of Ind, 1776. Visit the rec.hunting and rec.hunting.dogs FAQ Home Page at: http://sportsmansweb.com/hunting/
Response:
Jonathan, what is the scientific basis for making a claim that a certain cartridge is more inherently accurate than another? I’ve heard this before in regard to the .308 family of cartridges, and also the 6.5 x 55 Swedish. You mentioned this obliquely in a recent post and, since I respect your objectivity, I’m wondering what your reasoning is. (I’ll post this also to the group so all might benefit.) John Hanka Minneapolis MN USA Visit the rec.hunting and rec.hunting.dogs FAQ Home Page at: http://sportsmansweb.com/hunting/
Response:
>Jonathan, what is the scientific basis for making a claim that a certain >cartridge is more inherently accurate than another?
It’s not a scientific basis, so much as empirical from which the following hypothetical conclusion is drawn: cases that are short and fat are more accurate than long thin cases, and this is because they result in more uniform burning of the powder. >I’m wondering what your reasoning is. (I’ll >post this also to the group so all might benefit.)
I’ve debated this point (that cartridge A is ‘inherently’ more accurate than cartridge B) many times, and been persuaded to this line of thinking. In this debate, we make the presumption that the rifle under test is of the finest quality (i.e. a custom target rifle) and *not* a randomly selected factory made rifle. The empirical data produced by target shooters has shown that the 308 is an inherently accurate cartridge – and that’s why most of them who shoot full bore (high power) use 308. The same is true of some other cartridges, such as the 222 Rem: it is inherently more accurate that the 223 (whch is slightly longer). But note that the 22PPC is held to be more accurate than the 222, which is why is replaced the 222 as the cartridge of choice for bench-rest shooting. Note also that the PPC cartridges are short and fat. The 6.5 Swede is an oddity, according to the above theory, since it has a reputation for accuracy but cannot be described as short and fat. However, ‘accuracy’ can be a relative thing and since the Swede is mainly used as a hunting cartridge, maybe that indicates what is meant. I have no personal experience of the Swede, but I note that in this country and in the USA it isn’t in the forefront of target shooting. Maybe our Scandanavian friends can comment? –Jonathan Spencer Keith Borer Consultants – Forensic Scientists Mountjoy Research Centre, Durham, DH1 3UR, England tel: + 44 191 386 6107 fax: + 44 191 383 0686 Lat. 54 34.24 N Long. 1 20.17 W Visit the rec.hunting and rec.hunting.dogs FAQ Home Page at: http://sportsmansweb.com/hunting/
