What are the most EFFICIENT rifle cartridges?

[steve white]

By efficient, I mean which cartridges move a bigger bullet with less powderl, while providing greater velocity without increased powder capacity. For example, a 30'06 will move an equal weight of bullet faster and with less pressure than a 270 with equal loading, while a 35 Whelen will move a bigger bullet than the 30'06 at velocity for the heavy weight that the 30'06 can't match without exceeding safe pressure. (as well as the '06 requiring more powder to try and match it)
It seems to me that the more a cartridge is necked down, the less efficient it becomes? Yet we can't all just shoot straight walls, can we?
I also sometimes confuse a "balanced load" with an efficient load. A 7X57 is balanced--recoil is such that you could probably shoot it off your chin, yet it is a great killer in the field. But an 8x57 can launch a bigger payload (though with more recoil) and a 9.3X57 greater still. Is this why the 358 Win. is so good in performance?

What are your votes for most efficient cartridges? This may accidentally or otherwise pit magnums vs non-magnums.

 

[Doug Hamilton]

By efficient, I mean which cartridges move a bigger bullet with less powderl, while providing greater velocity without increased powder capacity. For example, a 30'06 will move an equal weight of bullet faster and with less pressure than a 270 with equal loading, while a 35 Whelen will move a bigger bullet than the 30'06 at velocity for the heavy weight that the 30'06 can't match without exceeding safe pressure. (as well as the '06 requiring more powder to try and match it)
It seems to me that the more a cartridge is necked down, the less efficient it becomes? Yet we can't all just shoot straight walls, can we?
I also sometimes confuse a "balanced load" with an efficient load. A 7X57 is balanced--recoil is such that you could probably shoot it off your chin, yet it is a great killer in the field. But an 8x57 can launch a bigger payload (though with more recoil) and a 9.3X57 greater still. Is this why the 358 Win. is so good in performance?

What are your votes for most efficient cartridges? This may accidentally or otherwise pit magnums vs non-magnums.

I know that some.of the gun writers of the past were fixated on the concept of what an efficient cartridge was. I am embarrassed to admit that I have never really understood the term. I had a kind of vague idea that it had something to do with moving a given bullet weight at a given speed while using less powder than another cartridge. I still don't know if that is correct. I'll be watching this thread to see what some of the more knowledgeable members have to say.

 

[Tundra Tiger]

I'm with Doug on my understanding of this. I guess I'm something of a simpleton. For me "efficient" = consistently kills animals within the parameters of how I hunt.

 

[dgr416]

The 375 winchester is about the winner .It pushes a 220 gr bullet at 2400 fps with about 37 grs powder .I love this little cartridge in win 94 bb weighing only 6 pounds with very little kick .The 338 federal is also another one 50 grs powder to move a 200 gr bullet 2600 fps .

 

[RedTag]

Magnum cartridges below .375 caliber aren’t about efficiency; they’re about maximizing power at longer distances. That’s why I say if you really need a magnum just a get a full length magnum and let it rip. If you want efficiency, cartridges like 7x57mm, .308 Winchester, and .35 Whelen will get it done in their respective weight classes at ordinary distances.

 

[mdwest]

I know that some.of the gun writers of the past were fixated on the concept of what an efficient cartridge was. I am embarrassed to admit that I have never really understood the term.

For me it’s a combination of lack of understanding along with a lack of caring…

In days long past I did quite a bit of “precision” and long range shooting, both professionally and personally.. but in those days I was limited to very specific factory loadings for a limited number of calibers… so efficiency meant nothing to me.. I just wanted the most accurate and the most precise shot possible out of whatever rifle I was using at the time..

Fast forward to today… probably 70% of the shooting I do is tied to hunting and hunting rifles.. I’d guess 20% is nothing more than recreational.. and maybe 10% is dedicated to maintaining defensive skills..

With the hunting guns maybe there’s a reason to concern myself with efficiency.. but if there is, I haven’t found it.. I use a 308 for the overwhelming majority of big game… I’m sure there are more efficient cartridges out there.. but for the game I’m shooting and the distances I’m engaging, it’s really no concern to me.. the animal isn’t going to be any more or any less dead as a result of squeezing out a few more FPS with a few less grains of powder at slightly less PSI and slightly less recoil, etc… and if the 308 isn’t enough gun, I’ll step up to my 300 mag… if it’s too much gun, I’ll step down to my .223… and not really worry if there is a more efficient 300 mag than mine or .22 center fire than mine..,

In my mind efficiency is a matter for ammo designers and manufacturers.. if they can produce the next gee-whiz 30 caliber magnum that’s 10% more efficient than a 300 prc… cool! Maybe that new cartridge will become the cartridge of choice for the next generation..

But for me.. I’ll just stick with what I have and what I know.. my bank account finds that more efficient

 

[Schüler Jumbo]

.257 Roberts Ackley Improved

 

[dougfinn]

I’m always amazed at how little powder the 8x57 Mauser uses to produce the energy it does.

 

[longrangehunterII]

The Bore-Ratio is why a ‘06, 338-06, or Whelen can push a heavier weight bullet faster than its counterpart.

IMO a 6GT, Dasher or 22 ARC would be considered just as efficient when going smaller diameter in bullet size.

Just as a 300 Norma Magnum is far more efficient in pushing heavy 230-245 grain bullets faster than a 30-378 Wby. Which requires 20 grains more powder to do the same velocity.

 

[mark-hunter]

Most probably Hornady superformance line will fit description best, with muzzle velocities faster then average.

And generally family of 7mm cartridges have the best ratio of trajectory, and sectional density (penetration). Various 270's, 284's, European 7 mm's, etc

 

[Accidental Villain]

Its a case by case thing this, isn`t it..
Swedish magazine Vapen once published a test done by a German hunters association to measure penetration capability of various popular calibers on huge wild boars. All using the same bullet type/brand of course namely Rhino bullets. These are definitely top top bullets in terms of penetration.
They also used correct bullet weights for the various calibers, like for 308Win they used 165grain, 150 grain for 270Win, 286 grain for the 9,3`s and so forth.
The test medium was built to exactly duplicate a monster European wild boar and not some idiot ballistic gelatin or whatever, so the test definitely had my attention.

Anyways, only two calibers was capable of passing thru the whole thing and proceed into the test medium behind. Namely 9,3x62 and not a surprise at least to me 8x57JS. I believe the 9,3 went something like 1,5 inch further than the 8mm.
6,5x55, 6,5x57, 7x57, 9,3x57, 270Win, 7mm08 and some others was in this test. One should not jump on to many conclusions from this I think, but again, I was not surprised about the 8x57 performance having using it for a while. And the x57 case tops out at about 8mm in terms of penetration.

 

[Hunter-Habib]

Here are mine:
7x57mm Mauser
.30-06 Springfield
.375 Holland & Holland Magnum
.505 Gibbs
.600 Nitro Express

 

[Mark A Ouellette]

Earlier this year @Tug provided a lot of deep analysis on why efficient cartridges are better than old trusted inefficient rounds like .375 H&H, .416 Rigby and so on. While I respected his effort I thought his hypothesis was silly at best. Considering the cost of a dangerous game hunt, a quality rifle to hunt with, and the limited amount of practice most shoot (200 rounds over a year prior?) with a dangerous game rifle, the efficiency of powder required to develop xxxx foot pounds of energy is not relevant.

I’ll take effectiveness in dangerous game cartridges over efficient any day! That stated, I prefer a .416 Rem over a .416 Rigby because the Rem produces less recoil and for some rifles, affords an extra round in the magazine than the venerable Rigby. The fact the .416 Rem requires less powder isn’t much of a concern for me. As for the .375 H&H, I’ll take it and you can take your chances.

To give @Tug credit where credit is due, here are his threads,

https://www.africahunting.com/threa...e-cartridges-you-didnt-know-you-needed.90013/

https://www.africahunting.com/threads/the-best-big-bore-cartridges-ever-created.90656/

 

[BlueFlyer]

Interesting thoughts - previously I created a table for the Taylor Knockout values. It was a simple task to add another column that divided the energy by the weight of propellant which basically tells you how many Ft/lbs of energy achieved per grain of propellant. Refer to the last orange column.
The standout from the data I have is the 458Lott, closely followed by the 458W, looks like straight wall cartridges are very efficient.

 

[odonata]

For me personally, the importance of efficiency at the rifle end will always be superseded by effective terminal results at the target end. Some people like to use the bare minimum that will work when everything goes right. I prefer to factor in enough overkill to still produce a bang-flop when everything goes wrong. Basically as long as there isn't the annoying flash of a huge fireball from excess powder burning outside the barrel, I don't really think about efficiency much.

Having said that, one of the cartridges that I've gotten really good results out of is my 6.5x55. Mild recoil. Emphatic kills with a 140gr Partition. It feels like it's punching above its weight well for the hunting that I do.

 

[Elkeater]

When I think of “efficiency” in rifle cartridges I typically think of how much powder am I burning for velocity. One of the most efficient cartridges available today is in my opinion 6mm ARC. I love this little cartridge (ya I know the opinion on .243 win around here). It’s my go to hog, javelina, predator cartridge and i wouldn’t hesitate to use it on deer too. It launches a 103gr ELDx out of my 20” barreled rifle at about 2710fps. No it’s not as fast as a .243 Winchester but it also is only using like 27gr of powder to do that. So what if I lose a couple hundred FPS muzzle velocity. I can have a rifle that sips powder which is getting expensive for us reloaders today and still gets the job done.

Other efficient cartridges are 7-08 rem, .308 win. .223 rem, .280 AI, and 7x57. I’m sure there are plenty of others.

But we are talking about shooting here so I also like to have fun and burn powder and sometimes that doesn’t involve being light with the powder scale.

 

[Nosler guy]

I find it very interesting - as soon as "efficient" is mentioned, it seems like the 7X57 pops into the conversation. I'm a big fan of the 7mm cartridges and nothing wrong with the old 7X57- actually a pretty big fan.

But if you are talking efficiency, the 7mm-08 pretty much trumps the old military case at every bullet weight. If you browse over loading data (assuming you are using similar test rifles) - the 7-08 pretty much trumps the 7X57 at every bullet weight, easily producing velocities equal too or more often above the 7X57, and just about always with a grain and a half or two less powder.

Not that it matters to me one bit - "efficiency" doesn't even enter into the equation when I take to the field. I like to get things done, I want my game on the ground. So I use what I consider "enough rifle", and more often than not, take it up one step more. MDWest had a good post about that, agree with what he was saying.

 

[fourfive8]

You’ll need to develop charts for each cartridge of interest based arbitrarily on at least two common barrel lengths and at least two bullet weights. Pick 20 inches and 24 inches for bbl lengths. Each chart would plot the ratio between bullet KE at muzzle against incremental changes of powder charge. The volume of data could be fairly large and the compilation time consuming. Cutting the increments of powder charge down to maybe 4 logical mass quantities and two bullet weights would help simplify process. Data could be presented in form of curve or bar graph for each cartridge and each barrel length.

 

[Nhoro]

There are a lot of variables involved.in general, larger diameter bullets are more efficient. Bigger area experiences a larger force at the same pressure. Overbore cartridges waste powder. So straight wall big bore rifles will be most efficient 458 win mag, lott and then 500 NE etc.

Then you have variables- powder burn rate will effect efficiency. Barrel length because you need full burn. Bore friction- so light for calibre bullets will be efficient at the muzzle but junk downrange.

If you download Gordon's reloading tool for free, you can play around with variables and see. You will see each changes changes everything else.

 

[Noah_McCoy]

7x57 Ai, I’ve always understand efficiency” of a cartridge as getting the most velocity while not being overbore.