Why do some cartridges seem to be more inherently accurate than others? Put another way,what makes some cartridges easy to get a good load for, no matter the gun. For example I always here people say that the 308 Win. and the 243 are "forgiving" in working up loads. Just curious as to why.

There is no big difference in my opinion. As long as the rifle is made right it will shoot well with well made components.

So if someone would say that a 6.5 jap does not shoot as well as a .220 Swift I would look at the care taken to make the rifle and ammo.

I've heard a theory set forth on different occasions that short cartridges are usually more accurate than equivalent longer cartridges (.308 Win and .30-06 Springfield are good examples) because the primer is igniting the powder more uniformly in the shorter case. I have heard this from people who know a lot more about guns and shooting all the way around than I do and it sounds like good logic, but I don't know how a person would prove it.

Hot Core,

You must mean that such cartridges are like a optimum or universal load for that gun or bore?

AAARRRRRGGGGHHHHH!!!!~!

Don't sic him on me, 99 !

Dan

Actually Hotcore makes a couple of good points, but it's unlikely he'll accept any kudos from me...

I agree with you guys that the presumed "inherent" accuracy of short, fat cartridges is more myth than fact.

My own idea is that the short, fat cartridges are generally more efficient, and can produce more velocity with medium burning powders than the longer shells can. That means less recoil for a given bullet weight at a given velocity.

With less recoil, people shoot better. I believe that may be one of the big reasons that the .308 has eclipsed the 30-06 in shooting matches.

I can get 1/2 MOA out of my 1972 Remington 30-06 ADL, with the universally excellent 57.5 grain charge of 4350 pushing a 165 grain bullet. And I've seen other 30-06's turn in incredible groups--every bit as good as many .308's.

That said, in order to get 2600 fps from a 168 grain match bullet in 30-06, it requires a charge with a harder "kick" than does the .308, and I believe that this recoil--no matter how tough the shooter believes himself to be--equates to more flinch, and less accuracy. In fact, the more a rifle recoils, the harder it is to keep the recoil cycle repetitive, which is of course necessary for good accuracy. But it can be done, and when it is done, heretofore thought "inherently INaccurate" cartridges can turn in some surprises.

Hey Hotcore, you contribute many good things and much experience to this forum, and believe it or not, it's good to see you back around... So... No punching below the belt, but other than that, come out swinging!

Dan "universal MUC load" Newberry
green 788

Well, I'm firmly in the camp of "inherently accurate" cartridges. That said, I don't buy that "short and fat is where it's at" either.

Consistent ignition, that's where it is really at. Violent ("hot", if you will) primers are needed to ignite long powder columns. Problem is, the hotter the primer, the more inconsistent the ignition.

Personally, I think that is because in long cartridges, because powder gets shoved into the barrel, where pressure remains lower, and therefore burn rates are both lower and more inconsistent.

A short column, ignited with a mild primer, and "all" the powder burning in the case, rather than the barrel, that's where it is at. Wether that's a 222 or a 6BR. JMO, Dutch.

OK, so when Mike Walker designed the 222, did he know that the cartridge he was designing was going to be "inherently accurate"? Same question can be asked about the designers of the 308. I kind of think they turned out to be highly succesful experiments that led to the design of new cartridges that turned out to be "inherently accurate", the PPC's being a prime example.

Hotcore writes: "Anyone who has ever loaded for more than one firearm in the same caliber knows the old Rookie Concept MUC Load(magical, mythical, mystical universal charge load) concept is "Full of Beans". W-a-y toooooo many variables for it to have any merit."

I suppose Paul Box, senior ballistics tech at Sierra, is "full of Hotcore's Carolina BBQ beans" as well. I've posted this before, but since Hotcore asked for it, he'll get it again...

I emailed Paul and inquired as to the concept of universally good load recipes. Following is his reply. He can be reached at 800-223-8799 for comment.

Hi Dan,
I agree.There are certain loads in every caliber that will produce a vibration pattern that seems to allow the bullet to leave the muzzle at the same point of that vibration.Usually if a load won't shoot in a rifle that has been known to be a good load in others,there's other problems with the rifle in a barrel being ho-hum,out of round chamber etc.These kind of rifles might shoot something else off the wall so to speak,but likely it'll be an uphill job finding it.Ken Waters made a fair piece of change with this idea in his pet load series.I've given out thousands of loads over the years that have proven to be very accurate in other rifles.You bet it works.
Paul

So maybe all of Hotcore's rifles have ho-hum barrels and out of round chambers?

Dan

Is there any connection why the 308. shadows the 30/06 and the 280rem. shadows the 7mmrem mag?
How many cartridges can shadow thier bigger brothers.

Hey craigster, Absolutely excellent thought provoking questions. I remember them being discussed by my Elders when I was quite young.

craigster, "OK, so when Mike Walker designed the 222, did he know that the cartridge he was designing was going to be "inherently accurate"?"

I believe by the time he and Remington got ready to release it, Mike Walker was confident about the "accuracy potential" in relation to the other Varmint Cartridges available back then.

If you look back in the history(aka old Reloading Manuals will help and info from old folks), most of the Cases preceeding the 222Rem/222RemMag design had a good bit more body taper. Cases like the 22Hornet, 218Bee, and 225Win were available in factory rifles, but a lot of them(perhaps most?) were chambered in lever actions too. They fed well for their actions and were "fairly accurate". Of course, chambering them in Bolt Actions increased their accuracy potential.

Hard for some folks to remember, but the 22-250Rem and 220Swift were not as common, because they were pretty much made up by local Gun Smiths. This means the variation in tolerances was wider and at the whim of the Gun Smith doing the chamber cutting.

(The first Wildcats I messed with had names like Barrickman and Hale because they were the local Gun Smiths making them.)

So, Mike Walker and Remington had the opportunity to "totally control" the 222 cartridge and chamber dimensions, plus stick them in a Bolt Action.

No telling how many actual "case volumes" were tried on the basic 222 Head Size. Having heard the debates when it was all new, the Elders tended to think a good bit of the "case volume" issue was selected because of the Velocity potential using Powders of that era. I seem to remember tham saying the average 3200fps 50gr bullets and 3300fps 45gr bullets(of that era) would work just fine at 300yds.

And remember, scopes were "uncommon" back then. Then couple the words dependable, repeatable adjustments, nonshifting reticles, weather tight with "scopes" and you were close to none made that anyone could afford.

So, it seems to me a whole lot of things came together for the 222s that worked in their favor. Even the "Custom Bullet Makers" like Vernon Speer were beginning to make extremely accurate 22cal bullets.

...

craigster, "Same question can be asked about the designers of the 308."

The 308Win has another interesting history trail. Driven by the Military's desire for a cartridge capable of duplicating the good old 30-06 in a lighter rifle.

Huuumm, what to do? Well, the 300Sav with a "new" Double Base Powder would fit the bill. But, the Pressure would need to be increased to get to the 30-06 velocity.

Double huuuumm, if the 300Sav case was "altered slightly", new rifles could be offered to the public too. And it would be possible to hype the 30-06 performance in a shorter, lighter firearm. (Does that sound familiar to the WSMs and SARMs?)

And, the 308Win actually hit the "pubilc" prior to the 7.62NATO reaching the Military. Amazing!

Tooooooo good to be true!!! Crank them out - they will come get them. And so "we" did.

...

craigster, "I kind of think they turned out to be highly succesful experiments that led to the design of new cartridges that turned out to be "inherently accurate", the PPC's being a prime example."

Other than adding, "extremely well well thought out and well engineered", I completely agree!

Thanks for an excellent post, Hotcore--I mean that!

You probably think I'm being sarcastic, but I'm not. You can be very informative, and a joy to read--when you're not thumping me over the head with your banjo, that is!

EEEEOOOOOWWWWW!!!!

Dan

kynadog, the more efficient a cartridge is, ie, the better its' powder capacity balances with the bore size and powder being used, the easier it is to find a powder/primer/bullet combination that shoots well. This is amother way of saying that there are more acceptably accurate combinations, I guess. For cartridges that have powder capacities less well matched to the size of the bore, the less acceptable combinations exist, hence more experimantation is needed to find an optimum match of bullet/primer/powder. In the case of extremeley large capacity cases, as compared to the "expansion ratio" of the bore, barrels have actually lost gilt-edge before the best or most accurate load was found!!!

PS: the .225 Winchester came at least a decade AFTER the .222 Remington!! But Winchester WAS still making the .220 Swift in 1950!!

[ 01-28-2003, 23:25: Message edited by: eldeguello ]

New board member here...
I'd like to offer my perspective as a Highpower Competitor on one of the points brought up regarding accuracy of the 30-06 vs 308.

While I'm sure the reduction in recoil has part to do with the 308's ascendance, it's widely acknowleged that the 308 was more accurate than the 30-06 due to it's being able to achieve near 100% loading density. It was well established that the position of the powder in a case with significant airspace could effect velocity and accuracy. In the old days, it was not uncommon for shooters to have a routine to ensure the powder came to rest in the case consistently before firing.