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Understanding cartridge efficiency

I think to determine the efficiency of a cartridge, you should factor in the task at hand. If that task is shoot small game at 60 yards on a calm day, the .22 long rifle would be at the top of the list. If the task is to put down a tough target at 2000 yards, in windy conditions, then barrel burning "inefficient" cartridges will be the most efficient.
 
stormc, that's not efficiency, but reasoned judgement.
Truly, efficiency itself would barely influence this (if at all).
But there are also somewhat hair splitting choices, that do lead to considerations in efficiency.

For me, considering two cartridges of same capacity, I run QuickLoad what-ifs and barrel life software to favor the better barrel life. There are a lot of other matters, bullets, brass, powders, action, barrel length, etc. Barrel life is just one factor. But it often follows efficiency and so that is important to me.
 
I really don't worry if my stuff is efficient or not. I want a certain bullet to go a certain speed and have a certain level of accuracy. I just use what it takes to achieve it. I personally would rather throttle down a bigger cartridge to achieve my speed than to hotrod a smaller one to get there. That's probably not efficient either. But barrels and brass last longer and that's more efficient on my wallet.
Shep
 
Efficiency becomes for me, can similar velocities be achieved in a truly smaller package. If we are using the same action with only a bolt stop magazine, in a 9lb rifle for a .300H&H, and a .300WSM have we gained anything. You still end up with a 200 grain class bullet doing 2900 fps from a 26" barrel.
I do think as we get into larger volume cases, driving lighter bullets, a shorter powder column will give us better ignitions.
People I have a lot of respect for, doing a lot more work with chronographs than most of us, are seeing something to case shape/velocity
 
Just a question from an interested bystander. If a 338 Norma can basically duplicate the ballistics of a 338 Lapua with the same 300 grain Bergers, wouldn't you say that the 338 Norma is more efficient if it uses less powder to achieve it's velocity? Please don't yell at me. I am interested.
I was looking at what the 338 SS was doing with the 250 grain bullets. From some of what I have read it is getting very close to the Lapua with a lot less powder.
 
I was looking at what the 338 SS was doing with the 250 grain bullets. From some of what I have read it is getting very close to the Lapua with a lot less powder.

Oh boy, here we go again ...

Brace yourself.jpg
 
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Just a question from an interested bystander. If a 338 Norma can basically duplicate the ballistics of a 338 Lapua with the same 300 grain Bergers, wouldn't you say that the 338 Norma is more efficient if it uses less powder to achieve it's velocity? Please don't yell at me. I am interested.

"IF" everything is the same (bullet, powder, primer, brass, barrel, etc.,), "NO".
 
I am gobsmacked to see why some members keep trying to deny or "work around" the most basic fact of ballistics. "Regardless of case shape, the same amount of powder, behind the same bullet, in a case of same interior volume will produce the same velocity".

That is fact. Period.

All the rest of his thread is opinions, advocation and use of bandwidth.
 
I was looking at what the 338 SS was doing with the 250 grain bullets. From some of what I have read it is getting very close to the Lapua with a lot less powder.
If it were infact running close ya but it's not, if you compare like the lowest node to the highest node maybe but high node to high node not close. I have ran far more 250's in the RUM case than the Lapua but they are very close, I run them at 3120 fps on the higher node and I believe the SS is right in the 2850 range maybe a touch more. There are guy who run the RUM at a lower node in the 2950 range but that's not really comparing capability for capability.
 
I am gobsmacked to see why some members keep trying to deny or "work around" the most basic fact of ballistics. "Regardless of case shape, the same amount of powder, behind the same bullet, in a case of same interior volume will produce the same velocity".

That is fact. Period.

All the rest of his thread is opinions, advocation and use of bandwidth.

Watching pressure curves and how we can manipulate time under the curve says there is more than just volume and pressure, is it gross changes no bit is there nuances there absalutely you can see them, heck you can feel them in the recoil impulse. How does that translate at the end of the barrel maybe it's a wash some times.
 
I am gobsmacked to see why some members keep trying to deny or "work around" the most basic fact of ballistics. "Regardless of case shape, the same amount of powder, behind the same bullet, in a case of same interior volume will produce the same velocity".

That is fact. Period.

All the rest of his thread is opinions, advocation and use of bandwidth.
A lot of these guys are simply comparing apples and grapefruit... They wind up their sharp shouldered wonder boomer until the primer pockets start to fail and decry victory as the thing ejected without welding to the bolt. The higher taper shallower shouldered cartridges can't be loaded quite as hot before they get sticky ejection so they'll not ever be run as hard by someone who has ever heard of the "shoe" test.
Modern brass has given us the ability to go quite a bit over the normal 65Kpsi top end without killing brass so what some think of as more efficient is really just more tolerant of overloading.
 
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