this might seem a simple question, but what makes an cartidge accurate? I am always being told that my 25-06 is not an accurate cartridge, a prime example is the 6mmBR against the 243, 222 against the 223 etc.
many thanks

Griff

well, this is the scraps of info (or old wives tales) I've been able to scrap up over the years:

22 cal has a bad habit of being very finicky with powder loads and accuracy, thus it's maybe less accurate

6mm/6.5 generally is supposed to have greater accuracy do to something or other (possibly gremlins who bet against the fellow shoot a 22 centerfire)

as to why a 6mm/6.5mm should have greater accuracy over a 257, bullet selection my guess has a lot to do with it. the longer bullets too are an advantage.

in all honesty i wouldn't know, i wouldn't even guess. I can tell you from experience my father had both a 222 and a 22/250, both of which would shoot straight when they felt like it, and finally my father go p.o.ed enough and turned the 222 into a 6mmbr which shoots like a house on fire all the time.

At the same token my friend Bill (the original Wild Bill for those of you old format guys) bought a 222 from one of the guys at the range and it was shooting like a house on fire until they took the scope off to sell it (or at least that's what they'd lead me to believe).

so there's some food for thought

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When in doubt, do a nuclear strike.

Fashions come and go in what people believe leads to inherent accuracy in cartridge design. Whoever told you that your .25-06 in not "an accurate" cartridge is poorly informed.

Current fashion holds that a short, fat powder train makes for better accuracy. This fashion is being promoted by people who have a vested interest in selling new guns and supplies for them, which, although a worthy cause in itself, has little to do with accuracy.

Only a few years ago, accuracy enthusiasts believed that long necks promoted better accuracy than short necks. Hardly anyone believes this today.

The advent of the PPC and similar cartridges and their percieved accuracy probably had more to do with their using small primer pockets (ie. less powerful primers), and the care with which their componets were made, than with other design features.

Accuracy has much more to do with the qualilty of the gun's barrel, the gun's construction, and the quality of the ammunition than with the design of the cartridge.

The main cartridge design factors that contributes to accuracy are those which allow consistency and repeatablility in the production of ammunition: (1) A reasonbly sharp shoulder for consitent headspacing, (2) reasonbly little body taper so that the cases do not tend to stretch so badly, and (3) fairly heavy wall construction for dimensional stability -- light construction is what contributes to accurcy difficulties in cartridges like .22 Hornet and .30-30 (in addition to other design flaws).

The 17 degree shoulder of your .25-06 is sharp enough to hold headspace, its body taper is reasonably straight, and its cases are plenty heavy. Is a .25-284 with its sharper shoulder, less taper, and heavier case inherently more accurate? Some would argue that it is, but in equally well crafted guns, there would be little difference.

And as for the latest "short powder" craze, I doubt the powder really cares how it's stacked in the chamber.

If people believe a cartridge is more accurate, then it probably will be just because of the care they give to the building of the rifle and the production of its ammunition. That belief sold a lot of PPC's through the years, and is now selling WSM's and Remington Short-Ultra's.

Admittedly, there are LOTS of marketing hype around accuracy. But there is also a little truth in some of it. Some case designs do have a slight edge.
A case were the flame from the primer just burns thru to the base of the bullet before it leaves the case is such a design. The firefront then moves out to the case sides and only burning gases, no unburnt powder, leaves the case. With this design the burning process is likely to be more eaven and potentially produce better accuracy and efficiency.
The problem is that to make any use of the small case design advantages, the rifle has to be very close to bench rest quality, and so must the shooter. Most rifles are not, neither are the shooters, because benches are rare in the woods and mountains... AKI

To what AKI has said, I can only add that, probably the most important factors that contribute to accuracy, is consistency and concentricity. This applies to all aspects of the shooting system except the nut behind the press, where only consistency applies

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Gerard Schultz
GS Custom Bullets

AKI __

Your theory (which you presented accurately) regarding ignition with respect to uniformity and efficiency of the "flame front" progression is one of many. Another is to ignite the gunpowder only at the flash-hole wherein the flame front would progress toward the base of the bullet. A third is to ignite the gunpowder at the base of the bullet wherein it would progress toward the base of the cartridge case.

All of these methods have their proponents, armed with at least some substantiating real data. Having done some experimenting myself with enlarged flash-holes, I can join the crowd in saying that practice also shows some benefits. But.... since most of this is still theoretical, we can only guess at what goes on during internal ballistics, hence I tend to stick with conventional practices and a cartridge case that is 100% filled with gunpowder (or augmented with filler).

Good shooting.

Robert

The best way to tell if a cartridge is accurate or not is to come back in twenty years. :-) There are a lot of theories as to what makes an accurate cartridge. Some of the theories border on fact and others, as posted above, are from sources that have a vested interest in your acceptance of their theory. With enough hype and a few well placed articles by "experts", just about anything can be sold. And, of course, there are a certain number of folks that must have the latest toy. Then the winnowing process begins. Will the new cartridge grow or will it fade away. The 7-08 was a wildcat developed for silhouette shooting (I understand) but its broader usefulness became apparent and Rem made it a house round. The 22-250 followed the same path. Why did these rounds grow while others faded? I would imagine with an expert gunsmith and an expert ballistian you could make about anything that you could cobbled up shoot well. But that isn't going to satify the masses. The folks that keep the arms industry thriving. It isn't uncommon to take a Ruger/Winchester/Remington/Savage in .222,.223,22-250,7-08,.270,.280,etc out of the box and have it shoot an MOA or very close to it. Without special tuning or exhaustive load development. What makes these production rifles in these production rounds accurate while many others have fallen by the wayside? Your guess is as good as any. Some of the things that the above cartridges have in common is they will all shoot well with a diverse selection of bullets, bullet weights and powders. Why? My answer to that is I haven't the slightest idea. Come back in twenty years and maybe I'll have some answers.

I couldn't agree more with beemanbeme, bodshawn, and Stonecreek on this subject.

I will also add something to the fire: Gun writer and theorists not only advertise with theories, but have you seen the latest? They go on little trips to Africa, kill some game with the cartridge they are advertising, then it all sounds like those cartridges are the best to accomplish that task. All you have to do is read some of the articles in the latest gun magazines. It is sad, but "newbies" will fall for that trap. They have no idea it is all BS.

BTW, I�m no fan of any particular theory, as they all actually are hypotheses.

This same discussion appeared on a finnish forum a few days ago. I guess some of you don�t read finnish, so I�ll repeat the bets parts:

There are a few findings that might shed some light on something.

1. The PPC is accurate with its short fat powder column. It is addmittedly easy to find accurate loads for. Despite this superiority finnish experimenters have found better designs than the PPC. Perhaps you should study some finnish, it�s as easy and fun as walking on boiling water. (No humor, I�m serious. For those accustomed to germanic languages, finnish is a true challenge) But the guys are hard to beat.

2. The 22 Waldog is slightly shorter but otherwise the same, so it should be even better. No, it�s a tough one. Four of my friends, all good BR shooters, have tried it and found it very selective on powders, bullets, seating depths and loads, i.e. The Lot.

3. Don�t remember the correct term for it, but a tube that protrudes from the fire hole almost to the bullets makes the powder burn from bullet backwards. This system gives better performance with the same charges. So, NOT letting unburnt powder out into the barrel behind the escaping bullet makes for efficient and even burning.

4. Straight cases are said to be inefficient compared to cases with shoulders. There is no way to keep unburnt powder within the case when the bullet starts moving.

My conclusion is that there certainly is something to be had in the "short fat" concept. However, extremes apparently wont work, so variables and parameters that are hard to understand, without putting a volonteer with a cellphone in a case and fire it, are present. This is, no doubt, one of the best gifts of The Creator to the shooting world. Otherwise it would be easy = no fun at all.

To get things straight:
1. MOA groups are not a sign of accuracy when discussing advantages of certain cartridge designs. The differences are much more subtle than that.
2. One thing is sure: a brute as a 30-378Wby will never shoot MOA in a standard production rifle with as little effort from the manufacturer as a 7,62x39 or the other anemic .222,.223,22-250,7-08,.270,.280 mentioned. This has nothing to do with inherently accurate cartridges, but with the problems to control the vibrations and precision of work in the rifle, as goes for the rifle manufacturer. And to find bullets that can take the violent handling in the barrel.
3. A 7,62x39 will always be easier to handle than a 30 Magnum within ordinary weights of the rifles.
4. Hype and lies was, is, and will be the fastest and easiest way to wealth. Greed rules as always.

These four points wont change in twenty years. AKI

Thanks for the support Gerard!

[This message has been edited by AKI (edited 12-02-2001).]

Short and fat, tall and skinny, magnum or standard?!?! The question is; what are you doing with this cartridge and what level of accuracy do you need? Fit a good barrel to a good action, bed and stock it correctly, use good sighting equipment and it will shoot accurately.

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LSF/375

thanks for all the replies guys, makes interesting reading,and certainly dispels some of the myths of specific cartridge accuracy.
the reason for asking the question in the first place was that i was having difficulty in loading the barnes x bullets, and was considering buying another 257 calibre in place of the 2506.
will persevere with 25-06 now and stay away from barnes x

many thanks
griff

I don't agree with Curtis Lemay. My most accurate rifles have been in .22 CF.

There was a lot of this guessing years ago when Harvey Donaldson and Landis and others searched for the perfect case. Then the sizing up idea was discovered by B&A I think and Sierra bullets came on the market. That was the end of accuracy problems.

The only case I know of that has a problem is the .22 Hornet and I guess better reloading dies may solve that.

Alot of it is BS. The 8x57 isn't supposed to be accurate but, I have a VZ24 with the barrel cut to 20" in a Ramline stock that shoot's in the .3's

Gsf 1200,
Post that story about the .3 cpable 8x57 on the Xtremeaccuracy site so I can watch the flame! Regards, Bill.

Where is the site? This 8x57 I have is amazingly accurate, I use mixed brass Win, Rem, and Hansen, and the groups open up to .4in, if I mix bullets Speer, Hornady, Sierra, all with differnet weights it shoots .5in. At 200yds though the groups open up quite a bit.

The most accurate case design was the .222 Rem. family of cases in the 1950's and 1960's. Most popular were the .222 Rem., unmodified, and 6X47 (.222 Rem. Mag. necked up to 6mm).

With the arrival of the .220 Russian case necked up to 6mm and blown out slightly the 6mm PPC was born and has dominated competititve benchrest shooting ever since.

Various attempts have been made to get the .25 and a few other calibers and cases to shoot accurately. They've invariably failed with few interested because of the cost of bullet making dies.

While a shortened version of the .22 PPC, the .22 Waldog or variants, has seen limited success, the average benchrest match will usually find 95% or more, usually more, using the 6 PPC.

The basic key to accuracy is not the case, however, it's the quality of the bullet. Since virtually all bullets for benchrest shooting are made in .22 and 6mm calibers it's not especially surprising that they're used by all compeititors.

Further, since a large percentage of benchrest shooters use the bullets they make themselves, typically in Rohrshach, Pindell or other dies, and use only .22 (to a lesser extent) and 6mm sizes, one returns full circle to the 6 PPC loaded with home made bullets.

Those who don't make their own bullets buy them from a variety of small to moderate sized custom bullet makers who use the same dies. Various experiments with making custom bullets using some mechanized feature to speed the process have failed, the most notable one being the Malsby bullets.

Experiments with the Remington .22 and 6 BR cases have generally failed not as much due to design features, but due to quality variations unacceptable in benchrest shooting, most notably variances in neck and case wall thicknesses and, to a much lesser extent, squareness of the base of case and various issues related to the primer pocket.

(These are the types of variations common in other cartridge cases where standard manufacturing procedures are used rather than the much higher standards used by Sako and others which have made .220 Russian and 6mm PPC variants. The "commercial 6 PPC case" that comes with a round of loaded 6 PPC Sako ammunition may, but often isn't, of the same quality as special lots made for benchrest shooters and also explains another reason for the "accuracy" of the 6 PPC....the cases are made to higher standards. Towards the end of the popular use of the .222 family of cases, for example, virtually all competitive shooters used the expensive RWS manufactured cases in .22 and 6mm calibers.)

The best choice in factory chambered rifles remain any member of .222 Remington family, 6 PPC family, or 6 BR family, in part due to case design, and (more importantly) the custom bullets available. The basic original Remington 722 action design (short action M700 of today) was the long preferred design of benchrest shooters until various custom action designs took over the scene in the 1980's. Probably the most accurate factory rifle with factory ammunition is the Sako chambered in 6 PPC, but it does not provide accuracy approaching competitive benchrest rifle standards for reasons beyond the scope of this message.

[This message has been edited by Plato (edited 12-03-2001).]

Of course we must remember that the BR and PPC class of cartridges were both developed for the benchrest crowd, who have a vested interest in inherantly accurate rounds. Slim