Another way to help decide which cartridge to use.

[lancetkenyon]

High BC means high SD....

They do not necessarily correlate. Take a look at various higher BC bullets in the .600 range, and you will see.

90gr .223 SMK, 140gr 6.5 HVLD, 190gr .308 NABLR, etc. All .600 BC, but greatly varying SD.

Bullet diameter and weight have to do with SD, not BC.

Better yet...
7mm 150gr
NABLR SD .266 BC .546
Part SD .266 BC .456

7mm 175gr
NABLR SD .310 BC .648
Part SD .310 BC .519

 

[cohunt]

Cohunt, please re-read my original post. Although 2000 ft-lbs of energy is a standard many people use as the minimum ethical impact for a standard rifle bullet (not a bow or pistol or spear or whatever) on elk, I picked it not because I believe it is "correct" but because it gives us a standard to compare various cartridges and bullets' impact at long range. I could have just as easily used 1000 ft-lbs, (which many say is the minimum ethical impact energy for whitetails) except that it would have required a lot more work since the Hornady charts only went to 500 yards, so I would have had to generate the data for each cartridge/bullet combo myself. I am NOT trying to dictate ethical ranges for your cartridge and bullet, I am just trying to demonstrate the relative downrange energy of a number of cartridges. It is a new way of looking at things for me, and pretty interesting; for example I just compared the 2000 ft-lb threshold between a 180 grain .308 Partition and a 180 grain .308 Accubond Long Range; leaving the muzzle at the same speed, the ABLR's 2000 ft-lb threshold is 150 yards farther out than the Partition's! From the same rifle!

I read your post, now read mine---you can't just pick some arbitrary energy number with out knowing how the bullet will act at that distance/velocity/energy

according to your "new look on things" ( just using an arbitrary energy number) a 150 gr FMJ bullet at a certain speed would have the same "set back distance" as a 150 grain varmint bullet, or 150 grain wfn hard cast lead bullet, or a 150 grain monolithic bullet as long as they all had the same muzzle velocity and BC--etc--etc --also SD doesn't mean a darn thing once the bullet deforms--once again it comes back to bullet construction--people handgun hunt all the time and most handgun cartridges ever reach the 1000 let alone 2000 ft lbs for your comparisons--I feel your "set back" should be based on bullet construction and accuracy limits

bullet construction should be your first choice before determining anything else IMO, to each is own I guess

 

[lancetkenyon]

Go tell the 6.5CM guys shooting a 143 ELD-X they can only shoot elk @ 110 yards......that will be awesome.

 

[Deleted member 103481]

Wait its 2k ft lbs now? Sometimes its 1800, sometimes its 1500, sometimes its said 1200 ft lbs. These elk need to hurry up and give us a definitive number so we can really hash this out.

 

[Deleted member 103481]

Go tell the 6.5CM guys shooting a 143 ELD-X they can only shoot elk @ 110 yards......that will be awesome.

290 max on a 7RM might ruffle some feathers as well

 

[FIGJAM]

I agree with your approach OP. Based on my experiences, I am ok with energy numbers lower than the stated 2000 ft lbs, but that approach is exactly what I use to determine what gun I am hunting with and how far my shots should be. Love the ballistic calculators and resources available to us now days.

 

[DDB TX]

They do not necessarily correlate. Take a look at various higher BC bullets in the .600 range, and you will see.

90gr .223 SMK, 140gr 6.5 HVLD, 190gr .308 NABLR, etc. All .600 BC, but greatly varying SD.

Bullet diameter and weight have to do with SD, not BC.

Lance, I stand corrected, you are right! And learned something today to boot, thanks! I found this article on Sectional Density to be a good read just now. One snip from it: "Note that SD is independent of a bullet's shape. All bullets of the same caliber and weight will have the same SD, regardless of their shape or composition."
https://www.chuckhawks.com/sd_beginners.htm

 

[DDB TX]

I read your post, now read mine---you can't just pick some arbitrary energy number with out knowing how the bullet will act at that distance/velocity/energy

according to your "new look on things" ( just using an arbitrary energy number) a 150 gr FMJ bullet at a certain speed would have the same "set back distance" as a 150 grain varmint bullet, or 150 grain wfn hard cast lead bullet, or a 150 grain monolithic bullet as long as they all had the same muzzle velocity and BC--etc--etc --also SD doesn't mean a darn thing once the bullet deforms--once again it comes back to bullet construction--people handgun hunt all the time and most handgun cartridges ever reach the 1000 let alone 2000 ft lbs for your comparisons--I feel your "set back" should be based on bullet construction and accuracy limits

bullet construction should be your first choice before determining anything else IMO, to each is own I guess

Cohunt, I never said that looking at the relative energy at range was the ONLY factor, or even the first factor, in choosing a cartridge or bullet, that would be silly. Of course bullet design is similarly important in making the choice. I just think it is interesting to see how various cartridges and bullets stack up against each other in downrange energy. I personally choose a cartridge first, not a bullet, for a given job, but if you want to choose a bullet and then the cartridge that works too.

 

[DDB TX]

290 max on a 7RM might ruffle some feathers as well

And I didnt even include the .243 Win numbers because the Hornady offerings dont even hit 2000 ft-lbs at the muzzle, or the 30-30 numbers because they don't either. But there are a ton of dead elk that would say those 2 rounds worked just fine. Again, the 2000 ft-lb number was just a convenient way to compare cartridges and bullets sold by one manufacturer, not a lecture on ethical hunting.

 

[Orange Dust]

Sectional density has nothing to do with downrange remaining velocity on target. BC does.

Sectional Density has always been used as a way to compare and estimate penetration of conventional cup and core bullets. Many of the new "Super Bullets" throw this out the window.

 

[Joefrazell]

I'd take a good hit with 1000 ft lbs over a bad hit with 2k. My point is to just be proficient with what you choose and however far you plan to hunt. Ve got a friend who killed a bull at 932 this season and it was with a 143eldx with around 700 ft lbs of energy left on target. Bull took a few steps and collapsed. bullet hit perfectly behind the shoulder and was found mushroomed beautifully on far sidea of hide. I say he's very very lucky. Also this was his first time shooting that rifle or anywhere near the distance. He was very lucky and says it was skill. O and I asked where he aimed and he said he aimed hi (when the guy he was with dialed) lol! He was very fortunate and so was the bull to not have suffered a bad hit. But my point is if you put it in the right spot it works.

 

[Orange Dust]

Here is the part no one, especially the young guys want to discuss. I will give in to the notion that the newly beloved 6.5 Creedmore will kill an Elk, Bull Moose, or even a Polar Bear, just as far as the shooter is capable of putting a hole through both lungs. The animal will eventually die. Does that make it a preferred or even suitable cartridge for those animals? Hardly. Here is the folly of the argument: Many Big Game animals are not shot during the best of conditions. They are often shot in poor light, poor visibility, gusty winds, steep angles, etc. Also, the further an animal is the more difficult it is to tell exactly how he is standing. The animal may appear to be broadside when it is in fact quartering to some extent. Add all these together and you need a safety factor for quick, humane kills. The bullet should be able to vitally penetrate whatever size animal you are hunting at whatever angle you are willing to take a shot, including shooting at a wounded one. Should also have a wound channel diameter that corresponds with the size of the animal. Figure your maximum range this into it and you have a bullet / cartridge combination that is not only suitable, but ideal for your situation. This can differ with every hunter. But if you are honest with yourself, the combo you choose will never let you down. Then I will add this to it: You can never, ever go wrong shooting the biggest gun you can shoot well if you want to hunt long range. Then you have the luxury of just needing to match your bullets to the game you are after, and adjusting your maximum range to that or your ability if shorter. And be honest with yourself. Usually no one is watching.

 

[Bravo 4]

DDB TX,
The Army comes up with their maximum effective ranges by meeting two criteria, probability of a hit (accuracy of the weapon/ammo combo) and terminal effects on target. I pretty much do the same thing, is my rifle capable of a high percentage shot and is the bullet going to have the effect I want when it gets there. Example: my .338 RUM will not shoot any high BC bullet to my desired accuracy, pretty much puts everything into 1.25-1.5" groups at 100. Not even really worth my time stretching it out. It has the "energy" (minimum velocity 1800 FPS and your 2000 fpe with a 300 grain Berger) to take an elk where I hunt to out past 1300 yards. I wouldn't even attempt that with this rifle because the probability of a lethal first round hit (even under idea conditions) would almost be what I would consider luck. The load I'm currently using is with a bullet that has no where near the BC but groups under 1 moa out to 800, where it also runs out of the "energy" that I find sufficient in cleanly taking an elk. So under favorable conditions 800 is the max effective range for that rifle/ammo. Now just because the rifle is capable doesn't mean the shooter is. Like I always say in my weapon classes, the number 1 factor in the max effective range of a weapon system is the nut behind the trigger!

 

[DDB TX]

Bravo 4, A great post, as are all posts on this thread, by the way, they hit many nails on the head. This whole idea of "setback" as a concept to evaluate whether to tote (for example) a 300 WBY or a 30-06 or a 26 somethingorother got started when I was elk hunting a'horseback in the Frank Church the second time, in 2014. Our very, very experienced outfitter would not allow any guns under a .308 caliber (not 308 NATO, rather, "thirty caliber") because he did not want to be chasing wounded elk on the Middle Fork of the Salmon country. He was OK with a 30-06 but not with anything smaller, and he limited 30-06 to 300-400 yard shots (horizontal; the bull I shot on our second trip was 300 yards on the rangefinder but only 150 horizontally, it is some steep country.) So it got me to thinking, what exactly is the difference between a 300 WSM and a 30-06 and a Wby 300, setback-wise? Turns out it is not that far, with a lot of bullets; and a good long way with some others. The magnums seem to benefit from the newer high BC for caliber bullets even more than the "standard" cartridges, especially if you reload; and with the wildcats, all bets are off. And as the Hornady data I set out demonstrated, there are some myths out there about the "incredible power" of certain cartridges that may not be that accurate.

Of course, as the 6.5 Creedmoor mania demonstrates, just because it is a wildcat doesn't make it a miracle pill. Not enough gun remains not enough gun, especially in those situations like Orange Dust set out above. That is where the energy at range information can help, for those not-so-easy or even (let's face it) bad shots.

But ultimately, as we all know, it is the shooter, and the technique, not the gun. Heck, Eskimos used to hunt polar bears with 22s. Makes for a dandy sucking chest wound, and not enough noise to rile the bear up.