Post by: baker5150 on September 07, 2017, 06:13:40 PM
When choosing a long range caliber, what velocity does a bullet need to be at to make an ethical kill on a deer or elk?
What other things are there consider?
I've seen, read, been told all kinds of different answers and wanted a take from this forum.
1800 fps seams to be a common trend, but I'd think expansion would make some difference.
I doubt I'll ever take a long range shot at game, I'm not a steady shooter, but I'm interested in learning the ins and outs.
Any thoughts?
Post by: h20hunter on September 07, 2017, 06:18:10 PM
Post by: baker5150 on September 07, 2017, 06:42:07 PM
Funny you say 1800. I load 165 gr accubonds for my 308. Once I verified my gun likes the bullet and powder combo i emailed Nosler. Right away they got back to me and suggested a minimal impact velocity of 1800. My loads, avg velocity at 500....per the dope I'm at 1803 at 500. Done.
I load 180 accubonds for my 300 wsm. It loves them with h4350. 700 yards its at 1802.
Hopefully this weekend I'll been hitting plates at that distance. I'm comfy at 400 off a bench. Anything more has been hit or miss. (Pun intended).
Post by: cboom on September 07, 2017, 07:35:05 PM
Post by: Bob33 on September 07, 2017, 08:02:32 PM
I believe Nosler is advertising velocities down to 1300. Most other bullets seem to call for 1800. I would feel more comfortable going slightly under that velocity with bigger calibers like the big 338's or 375's. Even if complete expansion doesn't happen it's still a big hole with lots of energy.They advertise the Accubond Long Range as having a minimum effective velocity of 1300 fps. The Accubond is rated as requiring at least 1800 fps.
Post by: cboom on September 07, 2017, 08:06:05 PM
I believe Nosler is advertising velocities down to 1300. Most other bullets seem to call for 1800. I would feel more comfortable going slightly under that velocity with bigger calibers like the big 338's or 375's. Even if complete expansion doesn't happen it's still a big hole with lots of energy.They advertise the Accubond Long Range as having a minimum effective velocity of 1300 fps. The Accubond is rated as requiring at least 1800 fps.
Good catch. Meant to say ABLR.
Post by: carpsniperg2 on September 07, 2017, 08:08:02 PM
Post by: crabcreekhunter on September 07, 2017, 09:40:13 PM
Post by: cboom on September 07, 2017, 10:10:00 PM
Post by: Magnum_Willys on September 08, 2017, 04:55:45 AM
Post by: jaymark6655 on September 08, 2017, 05:34:40 AM
Post by: h20hunter on September 08, 2017, 06:31:49 AM
A 30-30 has about 1400 ft lbs energy at 100 yards. I would want at least that on elk. It has 1000 ft lbs at 200 yards . I would consider that a minimum on deer.
This thread mimics the bro in law and I's duscussion the last few weeks as we shoot a,bit before modern. I handload for his 30 30. He confirmed his 100 yard zero then moved to the 6 inch plate at 200. Hit 3 for 3, smacked it good, done and ready. He is now confident to 200 all day and willing to extend to 250 max if things are perfect or maybe follow up.
Post by: BeWitty on September 08, 2017, 06:38:38 AM
I wouldnt worry about velocity as much as energy at a certain distance. I like to keep energy above 1000 ft/lbs at a mimimum for big game.Yes this.
1000 ft/lbs for deer
1400 for Elk.
You shouldn't simply generalize a velocity because bullet weights vary so much.
Post by: jaymark6655 on September 08, 2017, 06:49:11 AM
Post by: yorketransport on September 08, 2017, 07:10:07 AM
Just because you shot a 140gr 6.5mm bullet from a 1-8" twist barrel doesn't guarantee that it's going to actually give good expansion at 1800-2000 fps. Photobucket pulled all my photos from the bullet expansion thread that I had on here, but there were a lot of surprises with how bullets expanded at relatively low velocity. The vast majority of poor expansion results could be traced back to under stabilized bullets.
Bullets with higher stability factors (usually described with a SG value) penetrate more predictably and expand more reliably. Just because you have an SG of 1.4 and the bullets shoot straight out to 1000 yards doesn't guarantee that they'll give you expect at a lower impact velocity.
The best way to know how they'll expand at a certain velocity is to test them at that velocity. My testing a few months back changed how I recommend bullets for a lot of hunting applications. :twocents:
Post by: CP on September 08, 2017, 07:12:58 AM
http://www.ballisticstudies.com/Knowledgebase/Effective+Game+Killing.html
Post by: theleo on September 08, 2017, 07:28:12 AM
Post by: Magnum_Willys on September 08, 2017, 07:38:15 AM
Post by: birddogdad on September 08, 2017, 07:47:22 AM
Consider this thought:
if you take a 45cal pistol and put it against the side of a deer and shoot directly into vitals, will it kill it? Elk? if you think so, look at the data table for muzzle energy for the 45 and then bounce with your rifle ballistics table.. that would be the absolute worst I would argue as limits, and frankly would say that is too far but math would support effective kill if you hit effective kill area on game... this is just an example. the further out you go the angle of incoming projectile will affect how vitals are impacted as well.
Post by: Magnum_Willys on September 08, 2017, 07:55:46 AM
Post by: birddogdad on September 08, 2017, 08:04:34 AM
Interesting thought Birddog. Thats only 400-500 ft lbs.
just a spitball but I feel its fairly accurate, though not recommended for the "standard" shooter..
Post by: baker5150 on September 08, 2017, 08:49:09 AM
Post by: yakimanoob on September 08, 2017, 09:17:42 AM
It seems a bit counterintuitive, but Berger and Hornady have both told me that it's velocity, not energy, that should be used to gauge how the bullet will expand. Not sure exactly why this is the consensus, but I haven't do any testing myself so :dunno:
Baker, another thought to keep in mind is that, especially at long ranges, you should be using the G7 ballistic coefficients instead of the G1. The G1 BC of a modern boat-tail hunting bullet changes with velocity, and it's impossible for the models to predict those changes exactly. The G7 BC is constant (or close enough to constant, anyway) at all relevant shooting velocities. Most high-quality hunting bullets will have a G7 BC listed in the specs, and all the good calculators will allow you to specify that you're using G7 (although sometimes you have to open the advanced features to do so).
Post by: h20hunter on September 08, 2017, 09:25:08 AM
Post by: Bob33 on September 08, 2017, 09:33:07 AM
A 100 mph baseball has about 1700 ft/lbs of energy but isn't likely to kill an elk.
Here's a long winded but good read on the subject:
http://www.ballisticstudies.com/Knowledgebase/Effective+Game+Killing.html
Post by: 7mmfan on September 08, 2017, 09:38:57 AM
Velocity provides the oompf for expansion which in turn results in energy into the target. Like mentioned, its a dance between velocity, expansion aka bullet performance, and the resulting trasfer of energy. I find it fascinating.
This. And Bob33's comment is spot as well. The larger/heavier the object, the more energy it is going to carry regardless of its velocity. You need that velocity to provide proper penetration and expansion to transfer that retained energy into the animal to ensure a good ethical kill.
Post by: h20hunter on September 08, 2017, 09:51:50 AM
Post by: 7mmfan on September 08, 2017, 09:58:52 AM
Post by: h20hunter on September 08, 2017, 10:04:55 AM
Post by: yakimanoob on September 08, 2017, 10:11:52 AM
Velocity provides the oompf for expansion which in turn results in energy into the target. Like mentioned, its a dance between velocity, expansion aka bullet performance, and the resulting trasfer of energy. I find it fascinating.I'm with ya on finding it fascinating. I don't even have a long-range setup (nor the necessary skills to think about shooting past 350 or so) but I'm so much of a nerd I still like to learn about it (cf. the thread on the Coriolis effect in virtual campfire :chuckle:).
There's no way to untangle velocity from energy -- it's not as if mass changes for a bullet in flight, so velocity is really the only variable in external ballistics anyway. But it's literally energy that makes the bullet deform/expand so you think that would be the baseline metric that's used. But apparently velocity is more handy? :dunno:
Post by: bobcat on September 08, 2017, 10:12:46 AM
Post by: 7mmfan on September 08, 2017, 10:19:36 AM
Velocity provides the oompf for expansion which in turn results in energy into the target. Like mentioned, its a dance between velocity, expansion aka bullet performance, and the resulting trasfer of energy. I find it fascinating.I'm with ya on finding it fascinating. I don't even have a long-range setup (nor the necessary skills to think about shooting past 350 or so) but I'm so much of a nerd I still like to learn about it (cf. the thread on the Coriolis effect in virtual campfire :chuckle:).
There's no way to untangle velocity from energy -- it's not as if mass changes for a bullet in flight, so velocity is really the only variable in external ballistics anyway. But it's literally energy that makes the bullet deform/expand so you think that would be the baseline metric that's used. But apparently velocity is more handy? :dunno:
EDIT: Energy is not what makes the bullet expand, velocity and target resistence is. The velocity the bullet is traveling at, and the density of the target the bullet hits are what determine the amount of energy that is transferred at impact.
Consider this. I'm using fabricated numbers on the fly, these have no real life bearing on anything, just an example. A bullet is traveling at 2500 fps, and at the speed, carries a 2000 FP of energy. If, when the bullet hits it's intended target, it expands, plows through the target, and is found just under the skin on the far side. The bullet expended all 2000 FP of its retained energy given its velocity.
However, take the the same speed/energy, but the bullet design doesn't allow for full expansion at that speed. When this bullet hits the intended target, it zips through and disappears over the horizon. How much energy did it release on its target? 50% of it? 25% of it?
It's a lot of calculus and algebra and cosigns, and other stuff that I haven't played with in a long time, but the end result is, energy is a direct result of mass x velocity, and transferred energy is a direct result of bullet design and how much of the energy it expends on its target.
My understanding is that energy is a product of mass (weight) x velocity. The lower the velocity, the lower the energy. Take a 180 gr accubond and throw it as hard as you can at thing, its not going to expand or deform other than superficially. Fire it at 2000 fps, and it penetrates/expands, and destroys. The mass of the bullet needs to be traveling at a minimum velocity to perform.
What the minimum velocity is seems to be up for debate, but 1800 fps depending on the bullet design, seems to be the benchmark.
Post by: yakimanoob on September 08, 2017, 10:30:02 AM
My understanding is that energy is a product of mass (weight) x velocity. The lower the velocity, the lower the energy. Take a 180 gr accubond and throw it as hard as you can at thing, its not going to expand or deform other than superficially. Fire it at 2000 fps, and it penetrates/expands, and destroys. The mass of the bullet needs to be traveling at a minimum velocity to perform.
That's the gist of it.
Technically (kinetic) energy is half the product of the mass and the square of the velocity, so small changes in velocity have a much larger effect on the energy than small changes in mass. Mass times velocity is the quantity we call momentum and is a slightly different idea.
The oddity for me in using velocity over energy is that if you know one (and the mass of the bullet, which you always should) then you know the other. E = 0.5*m*(v^2). Or, v = sqrt(2E/m). It must be that velocity is just a more convenient metric because maybe an 85gr bullet with 2000 ft-lbs of energy expands much differently than a 180gr bullet with the same energy, but they expand similarly if they're both moving at 1800 fps. :dunno:
Post by: 7mmfan on September 08, 2017, 10:33:48 AM
My understanding is that energy is a product of mass (weight) x velocity. The lower the velocity, the lower the energy. Take a 180 gr accubond and throw it as hard as you can at thing, its not going to expand or deform other than superficially. Fire it at 2000 fps, and it penetrates/expands, and destroys. The mass of the bullet needs to be traveling at a minimum velocity to perform.
That's the gist of it.
Technically (kinetic) energy is half the product of the mass and the square of the velocity, so small changes in velocity have a much larger effect on the energy than small changes in mass. Mass times velocity is the quantity we call momentum and is a slightly different idea.
The oddity for me in using velocity over energy is that if you know one (and the mass of the bullet, which you always should) then you know the other. E = 0.5*m*(v^2). Or, v = sqrt(2E/m). It must be that velocity is just a more convenient metric because maybe an 85gr bullet with 2000 ft-lbs of energy expands much differently than a 180gr bullet with the same energy, but they expand similarly if they're both moving at 1800 fps. :dunno:
That equation tipped me over. I have baby brain, and lack of sleep and only 4 cups of coffee today. I'm bowing out. Carry on. :salute:
Post by: yakimanoob on September 08, 2017, 10:35:36 AM
EDIT: Energy is not what makes the bullet expand, velocity and target resistence is. The velocity the bullet is traveling at, and the density of the target the bullet hits are what determine the amount of energy that is transferred at impact.
Consider this. I'm using fabricated numbers on the fly, these have no real life bearing on anything, just an example. A bullet is traveling at 2500 fps, and at the speed, carries a 2000 FP of energy. If, when the bullet hits it's intended target, it expands, plows through the target, and is found just under the skin on the far side. The bullet expended all 2000 FP of its retained energy given its velocity.
However, take the the same speed/energy, but the bullet design doesn't allow for full expansion at that speed. When this bullet hits the intended target, it zips through and disappears over the horizon. How much energy did it release on its target? 50% of it? 25% of it?
It's a lot of calculus and algebra and cosigns, and other stuff that I haven't played with in a long time, but the end result is, energy is a direct result of mass x velocity, and transferred energy is a direct result of bullet design and how much of the energy it expends on its target.
My understanding is that energy is a product of mass (weight) x velocity. The lower the velocity, the lower the energy. Take a 180 gr accubond and throw it as hard as you can at thing, its not going to expand or deform other than superficially. Fire it at 2000 fps, and it penetrates/expands, and destroys. The mass of the bullet needs to be traveling at a minimum velocity to perform.
What the minimum velocity is seems to be up for debate, but 1800 fps depending on the bullet design, seems to be the benchmark.
I agree with the concepts you're getting at, just not the technicalities. It is only energy that makes the bullet expand, but I should have clarified that there are more types of energy than the kinetic energy measured in ft-lbs that we normally talk about. Technically it's mechanical energy between the target and the bullet that causes the bullet to deform -- the target is literally pushing the bullet into that shape. This mechanical energy ultimately comes from the kinetic energy of the bullet in flight of course, but like you said there's a LOT going on when it comes to terminal ballistics, and it doesn't necessarily make sense to measure the mechanical energy that deforms the bullet in terms of the kinetic energy it has right before impact.
Post by: yakimanoob on September 08, 2017, 10:43:11 AM
That equation tipped me over. I have baby brain, and lack of sleep and only 4 cups of coffee today. I'm bowing out. Carry on. :salute:
Haha, yeah I should leave the physics for another time and place. Sorry to side-track your thread, Baker!
Post by: Bob33 on September 08, 2017, 11:02:10 AM
That information is essentially accurate but misses a few key points.Velocity provides the oompf for expansion which in turn results in energy into the target. Like mentioned, its a dance between velocity, expansion aka bullet performance, and the resulting trasfer of energy. I find it fascinating.I'm with ya on finding it fascinating. I don't even have a long-range setup (nor the necessary skills to think about shooting past 350 or so) but I'm so much of a nerd I still like to learn about it (cf. the thread on the Coriolis effect in virtual campfire :chuckle:).
There's no way to untangle velocity from energy -- it's not as if mass changes for a bullet in flight, so velocity is really the only variable in external ballistics anyway. But it's literally energy that makes the bullet deform/expand so you think that would be the baseline metric that's used. But apparently velocity is more handy? :dunno:
EDIT: Energy is not what makes the bullet expand, velocity and target resistence is. The velocity the bullet is traveling at, and the density of the target the bullet hits are what determine the amount of energy that is transferred at impact.
Consider this. I'm using fabricated numbers on the fly, these have no real life bearing on anything, just an example. A bullet is traveling at 2500 fps, and at the speed, carries a 2000 FP of energy. If, when the bullet hits it's intended target, it expands, plows through the target, and is found just under the skin on the far side. The bullet expended all 2000 FP of its retained energy given its velocity.
However, take the the same speed/energy, but the bullet design doesn't allow for full expansion at that speed. When this bullet hits the intended target, it zips through and disappears over the horizon. How much energy did it release on its target? 50% of it? 25% of it?
It's a lot of calculus and algebra and cosigns, and other stuff that I haven't played with in a long time, but the end result is, energy is a direct result of mass x velocity, and transferred energy is a direct result of bullet design and how much of the energy it expends on its target.
My understanding is that energy is a product of mass (weight) x velocity. The lower the velocity, the lower the energy. Take a 180 gr accubond and throw it as hard as you can at thing, its not going to expand or deform other than superficially. Fire it at 2000 fps, and it penetrates/expands, and destroys. The mass of the bullet needs to be traveling at a minimum velocity to perform.
What the minimum velocity is seems to be up for debate, but 1800 fps depending on the bullet design, seems to be the benchmark.
First, a bullet that lodges on the far side and doesn't exit is much less likely to leave a blood trail for tracking.
Secondly, the issues of wound channel size, bullet cavitation, and hydrostatic shock also play roles in how quickly an animal dies.
A simple formula for the kinetic energy of a bullet is ( bullet_grains x velocity x velocity ) / 450,800.
Example of a 180 grain bullet at 2700 ft/second: (180 x 2700 x 2700) / 450800 = 2910 foot pounds of energy.
Post by: yakimanoob on September 08, 2017, 11:45:17 AM
A simple formula for the kinetic energy of a bullet is ( bullet_grains x velocity x velocity ) / 450,800.
Example of a 180 grain bullet at 2700 ft/second: (180 x 2700 x 2700) / 450800 = 2910 foot pounds of energy.
I just tried to figure out how this was the same as E = 1/2 m v^2 and got hit in the face by how incredibly *&$%ing stupid the imperial system is.
7000 grains = 1 lb(mass) = 32.2fps*1lb(force). Kinetic energy is measured in ft*lbs(force). So if you start with grains, you have to divide by 7000*32.2, which is 225,400. Once you apply the 1/2 part of the kinetic energy equation, you get the 450,800 in Bob's equation.
OR if we measured everything in metric, there would be no conversions to do at all. Mass of the bullet in grams, velocity in meters per second, plug into the equation and we're done. F&^%ing British units :bash:
Post by: kselkhunter on September 08, 2017, 02:02:17 PM
To the Op: Find out what the minimum impact velocity is for your chosen bullet from the manufacturer and how it performs at varying velocities (some manufacturers supply photos of recovered bullets at various velocities). And test them out at those ranges (Yorketransport did some good reviews on bullet performance). A low velocity impact that pencils through will still kill an animal if it hits the heart/nervous system....but that shot at long ranges in hunting conditions can challenge even the most experienced long range shooters.
I've witnessed wannabe long range shooters lobbing bullets at a bull over a half a mile away and missed so badly they killed the calf standing next to it. :bash: Not factoring how far wind can drift their bullet at those ranges.
A 168gr ABLR out of my 7mmRM will have over 1800fps of velocity at 800 yards and thus the bullet will perform and my custom ballistic turrets take the guesswork out of bullet drop calculations.....but if that bullet encounters a 10mph cross wind halfway across the canyon it will drift multiple feet. Lower BC bullets out of other calibers can drift 4 ft or more at those ranges. I'm not skilled enough to make those wind estimations, so don't take such shots myself.
But, there are plenty of guys on this forum that can make a long range shot and have the gun, caliber, bullet, and years of experience and regular practice range time to pull it off every time. They can give much better advice than I. But, I'd expect a bigger 338 caliber variant would give the best of all worlds in velocity and higher BCs to better resist wind drift at longer ranges, as long as bullet stability (ie twist rate vs. bullet selection, etc.) is also factored in.