How Much energy is too little?

[fta0303]

What's required to kill an animal depends greatly on the condition of the animal. A wounded, angry grizzly may take a lot more than one quietly resting. Certainly it depends on the size of the animal. There are great variations in size within a species, so a single criterion for a species must assume the largest. Energy is a poor indicator in itself: there is a great difference in killing effectiveness between a high velocity bullet that blows up on impact w/o penetrating and one of equal kinetic energy that does penetrate. What part of the bullet's energy is dumped inside the animal matters and where it is dumped matters also. If the bullet penetrates completely, then not all of its energy is dumped in the animal. The bullet's penetration depends on what it strikes in the animal. The reaction of the bullet to impact and penetration is presumably a big factor. And some say so is its velocity. Many factors affect the outcome. Small wonder that we seek a simple guideline. But I doubt that a simple guideline suffices. Unfortunately, you must know or learn what you are doing at a little higher level of detail. An energy cutoff by itself doesn't cut it.

Nathan Foster at Terminal Ballistics Research (https://www.ballisticstudies.com/) has much to say that seems sensible. He bases his conclusions on observed effect in the field. What comes out to this layman is that you need to know your rifle, your cartridge, your bullet and the effect of target distance and strike point. A premium bullet may not yield a premium effect if a strike point appropriate to the target distance is not selected. Nathan's experienced-based comments on the performance of various bullets in a given cartridge at various ranges are invaluable. There are a handful of important factors and you as a hunter must understand them. Homework is better than an energy cutoff value.

 

[trout004]

View attachment 556564

 

[3chester]

Does kinda make a guy wonder, where that energy goes when a .308 caliber 165gr Barnes bullet, fired from a 300 RUM, goes thru a 1/2 inch thick steel sheet pile at 100 yards and only leaves a 45 caliber hole behind.

 

[FEENIX]

Nebraska deer regs. requires 800 ft/lb at 100yd for rifle and 400 ft/lb at 50 yd for handguns.
Nothing is said about energy at impact.
Ranges where I am at can be really long

I believe they are minimum energies at points of impact (.22 cal) and an excellent guide/requirement.

 

[Mike D Texas]

This is because bullet deformation in a liquid like media depends on dynamic pressure so the animal is "hard enough" to expand the bullet. Basically, at a certain impact velocity, the "deer" is harder than the bullet as the material can't get our of the way fast enough and the bullet deforms. As the bullet penetrates and slows down it will stop deforming. You can impact steel plate at much lower velocity and there is plenty of energy to deform the bullet

Just saying - minimum expansion velocity alone is not an indicator of killing power any more than energy is stand alone

Lou

In animals, I disagree. Expansion, fragmentation and crushing of tissue and destruction of the CNS or vascular system is what kills animals.

Velocity is the driving factor for bullet upset, not energy.

 

[asd9055]

The gift that keeps on giving. No matter how many times this comes up, here or other places, it is always fun to watch, specially with an adult beverage.

 

[Mike D Texas]

The gift that keeps on giving. No matter how many times this comes up, here or other places, it is alwaus fun to watch, specially with an adult beverage.

As long as it's can discussed like adults it's fine.

 

[3chester]

MN , 410 shotgun slugs legal for Deer. Brenneke slugs are 1/4 ounce going about 1800-1900 fps. Federals 410's are only 1/5oz slugs but they easily kill a Whitetail deer inside 150 yards. So it's like about a .357 Magnum with an 85 to 125 grain cartridge, deer can't tell the difference, when hit.

 

[asd9055]

Questions:
If velocity alone kills, if I hit a deer with steel projectile of 0.1" diameter weighing I don't know, 30 grains, in the belly, with impact velocity of 1500fps, will the deer get killed?
Conversely, if I take a 15 lbs weight, hit a deer at approximately 6 miles/hour will the deer get killed?
I think you can not take one without the other. Its more complex and beyond my knowledge.
But I am always learning something new here.

 

[FEENIX]

Here's an excellent read from one of the best out there in the field.

https://www.ballisticstudies.com/Knowledgebase/Effective+Game+Killing.html

 

[6.5x300 WBY]

While kinetic energy and ft/lbs are perhaps related, the topic is ft/lbs energy….. which a the misleading term used by bullet manufacturers for many years. It gave us, the somewhat gullible, shooters a method to compare cartridges……however incorrect and useless it may be!

Absolutely. It will never die unfortunately.

 

[memtb]

Lou,
You are right. Expansion, if you get it, usually occurs within the first couple of inches of penetration. We see this in gel testing all the time. Modern rifle bullets are designed to have a wide range of velocities at which they will expand although expansion can vary widely according to the impact velocity. On the LE side of the house , especially in handgun bullets, expansion is not something we rely on getting 100% of the time. Variables such as the type of clothing a person is wearing or any other intermediate barriers can can affect expansion. Plugged HP's have a tendency to become FMJ's and will go completely through a 16" block of gel in all of the handgun calibers. Expansion in any bullet should never be considered a cure for poor shot placement or penetration.
I've killed some pretty large critters, very effectively, with heavy, solid rifle bullets.

I would "much" prefer to use my 460 Smith with my wide metplat bullet starting @1500 mv on a sharply quartering (rear hip area to offside front quarter) elk @ 100 yards than the same shot with an expanding (not mono) bullet from .243 Win……assuming equal bullet placement.

A lot can be said for deep penetration……ft/lbs energy be "darned"! memtb

 

[dogz]

Personally I'd never take that shot on an unwounded animal. In 45 years of elk killing and being around one heck of a lot of elk we've never had to take that shot!

Side note, I'm more than comfy if in that situation at that close or range of getting the bull take a peak back at me. If he did....then it'd be a Nosler under the ear and game over.

Way too many things can go wrong in trying Elmer's famous old "raking shot"......

Like I've said B4, at sooner or later the elk wins and I'm fine with that!

 

[dogz]

To the "Eneregy" question. I'm 65, haven't looked at a energy table since 8th grade back when I really thought that they meant something.

And old and long gone mentor said to me "put a good bullet in a good place, wreck the lungs and it's game over". For darn sure he was spot on. He was a fan of the Big 22's for hunting all of the big game that Montana has to offer. I grabbed onto what he said and have shot and been around several arks full of game from small big game like Lopes, Deer, black bear to sheep, goat, elk and a few more taken with the good old 22/250 and the Swift.

Furthest I can recall taking game with 55's-63's is 505 yards. I'd have to look at my log book but I'd think that 93% of the game we've taken with these rounds have gone straight down. Elk will generally take a few steps and pitch over.

Recently we had 49 one shot kills using the 63 Sierra and 60 Horn HP between 15 yds at the close range to a bit over 400.

Those bullets go in shred the lungs and boom done game over. Now freaking idea how much energy they carry at those ranges, never looked could give a hoot less about it. Just know that they're effective as anything else I've used.

Now when I go over 300 yds for elk I like to go to one of my Big guns either a 270 or my 7 Mashburn Super.

Last note, I was a 340 Wby nut for years, wore out two Schneider barrels. As much as I liked it I never found it to take elk out any quicker than my 270 with 130 Sierra BT's or my Mashburn with 150 NBT. Of note I should say that 700 yds is my outer edge for range I'll shoot on game.

Last last note............. it'd be kind of fun on these threads if one could only make one post!