What's the most efficient center fire cartridge?

[Stonechucker]

Looking to see what you guys think the most efficient center fire cartridge might be. I am thinking along the lines of grains of powder vs Ft lbs of energy. For instance I shoot a 357 Maximum with 26.5 grains of unspecified powder, and get approximately 1810ft lbs of energy from a 20 inch barrel with a 158 grain bullet. I would love to hear your ideas!

 

[dredd]

This is an interesting Can of Worms waiting to be opened and watch spill out uncontrollably.

I think that there has to be a specified Task associated with the question.

I could say that my 338LM flinging 250/gr bullets is the absolute most efficient cartridge for my intended purpose.

Let the fun begin!

 

[George P]

6mm BR on one of the various forms

 

[AJC1]

Are we talking about at the muzzle or at some arbitrary range like 500 yards. Things like bc will have a big difference at range.

 

[Ru4real]

223 Remington

3000 fps 69 grain bullet with 26 grains of powder from a 26 inch tube. What’s not to like?

 

[Stonechucker]

At the muzzle. I am taking ballistic coefficients out of the equation.

 

[Stonechucker]

It would be great to here how many grains of powder you guys are loading, and what muzzle energy you are getting. This is all just for fun by the way. I love ballistics

 

[AJC1]

460 weatherby gets a 552 grain bullet 1396 fps with 28 grains of unique for 2389 ftlbs

 

[Stonechucker]

Ajc1 that sounds like an awesome low recoil 460 load. I didn't know there was such a thing.

 

[AJC1]

45/70 same 552 bullet 14 grains unique for 1100 fos. It's only 1483 foot pounds but half the powder so way more efficient. That's 110 foot pounds per grain.

 

[Random 8]

Away from my books so I can't give specific numbers, but willing to bet a 9mm 124 grain over a max charge of titegroup or bullseye is near the top in terms of FPE per grains of powder. Wouldn't want to hunt deer with it though.

 

[AJC1]

Away from my books so I can't give specific numbers, but willing to bet a 9mm 124 grain over a max charge of titegroup or bullseye is near the top in terms of FPE per grains of powder. Wouldn't want to hunt deer with it though.

I would wager the same load in a 45 would give better results.

 

[Random 8]

I would wager the same load in a 45 would give better results.

Run the numbers. Not doing it here on my phone in the wilderness

 

[AJC1]

I did it was close. I assumed 1200 fps on your 124 that's very optimistic imo and 850 on my 230 45acp. The result was equal. Is 900 vs 1100 fps more realistic maybe but I was thinking low pressure would normally win out in effency with fast powders and larger bores.
They were both less efficient than the 45/70 load

 

[Skgreen]

Fired through my 26" bolt action, through your 16" semi-auto, or 'just by some numbers on paper'?

 

[JFrank]

6mm BR on one of the various forms

I will probably echo this gentlemen.
103 gr bthp
30.04 gr powder
2920 fps
BC is 525 ish
Super accuracy
What's not to like

 

[loadedround]

I would have to case the 158 GRSWC load in a 357 Mag.

 

[Blue68f100]

Anything that meets it intended purpose...... You have to have accuracy otherwise it's a waste.

 

[mcb]

Grab a copy of Quickloads and enter your favorite load and it will tell you what percentage of the potential chemical energy stored in the selected propellent gets turned into kinetic energy of the bullet at the muzzle.

 

[kalielkslayer]

So I load for the 7mm-08, .280 Rem and 7mm Rem Mag.

The 7mm-08 is the most efficient. I need 8-9% more powder to get 150 fps (5%) in the .280. Another 12-15% more powder above the .280 to get 300 FPS (10%) out of the 7mag.
But I usually carry the 7mag.

If I had a 28 Nosler, I would probably carry that.

I could even argue the .380 is more efficient than the 9mm; 33% more powder to get 20% more velocity. But I’d rather have a 9mm in my hand.

 

[AJC1]

The faster you try and push a round the less efficient it becomes. Those percentage gains bears that out exactly. The 308 on one end of the scale and 300 ultra mag on the other. I dont want to do all the math but I would bet the 300 bo shooting heavy subs does very well in this exercise. Removing bc from the equation makes it a paper drill at best. If down range was considered a 6arc or a 6mmbr would do very well with the 6.5 creed not far behind....

 

[Demi-human]

The most efficient cartridge would be the one that has the largest diameter piston(bullet) with the longest stroke(barrel) from a chamber that had the densest fuel payload. I think a straight walled cartridge, and like @AJC1 said not a hot one.
I like 45 Auto, I’ll go with that.

But if we didn’t waste energy out of the end, and the powder ceased putting pressure on the bullet as it exited, we’d need incredibly long barrels to get any kind of velocity outside of the barrel. But maybe no muzzle blast?
So, I’m more concerned with performance, not efficiency.

Super quiet, less than lethal rounds?

Or maybe...

In reality many cartridges are very efficient. The powder being burned and turned to plasma hot gases long before the bullet leave the bore. All of that pressure is captured and used while burning, just the “exhaust gas” is ejected.

Hmm, revolvers and their cylinder gap not withstanding perhaps.

 

[jmorris]

308 was the highest on this list at 67 ft/lbs per grain.

https://blog.westernpowders.com/2016/07/looking-at-cartridge-efficiency/

The data in #8 would be 85 ft/lb per grain.

Post #5 is 53 ft/lb per grain.

Post #1 is 68.3 ft/lb per grain.

6mm BR with 31gn pushing an 87gn bullet 3000 fps with 31 grains = 56 ft/lb per grain.

A 22 hornet with 12.4 pushing a 45 gn 2900 fps is 67.7 ft/lb per grain.

My 9mm minor load using 3.1 gn of N310 pushing a 147 at 890 fps is 82.9 ft/lb per grain.

A 25 ACP with 1.3 gn pushing a 50 grain bullet 850 fps is 61.5

A 22 short CB pushing a 30.5 grain bullet 700fps with .36 grains of powder is 91.7 ft/lbs per grain.

Winchester Dynapoint .22 lr pushes a 40 gn bullet to 1155 fps with 1.12gn of powder, beating them all with 105.3 ft/lbs per grain.

 

[Demi-human]

Winchester Dynapoint .22 lr pushes a 40 gn bullet to 1155 fps with 1.12gn of powder, beating them all with 105.3 ft/lbs per grain.

The undisputed king of straight wall cartridges!

And evidently the least wasteful as well, the 22LR!

 

[higgite]

The undisputed king of straight wall cartridges!

And evidently the least wasteful as well, the 22LR!

Read the topic heading again.