Questions for Form and other "small caliber for big game" folks

[mxgsfmdpx]

My 20" 6CM hits about 1800 FPS at 825 yards using factory 108 ELD-M. That is with an Ultra 7 on it and at an elevation of 5500ft.

This had me crunching some numbers.

My Tikka 22 Creedmoor with the factory cut/threaded 19” barrel and 80 ELDX hits 1800 FPS right at 900 yards at 5,000 feet and 50 degrees. Energy shows somewhere around 600 ft lbs. Wind drift for full value 10 MPH shows 1.5 MILs at 900.

My Tikka 6 Creedmoor with factory cut/threaded 18” barrel and 108 ELDM hits 1800 FPS right at 800 yards at 5,000 feet and 50 degrees. Energy shows somewhere around 775 ft lbs. Wind drift for full value 10 MPH wind shows 1.3 MILs at 800.

 

[roadrunner]

A mature cow elk went 8 yards and died in less than a minute. I put 4 shots into it with ease and though my shooting form and position was far from ideal, I still watched it all happen through the scope, which I had never done before.

Did the same thing once with a .270 WSM and a 140 gr bullet, prone on rim rock in 8" of snow. Cow went 10 yds or so with one shot. "Jellyfied" the lungs. Shot was 295 yds with approx 125' of elevation change downangle.

 

[Flynhunt]

Have you listened to the two part podcast from Exo with Form discussing this exact topic in depth for 3+ hours? If you haven’t, you really should, it was pretty much made to address every concern you’ve raised. I say this after acknowledging that I was basically you about 2-3 years ago. I was going to build a 7mm Rem Mag for elk because it’s “good elk medicine”.

Then I got on rokslide and started learning all about the idea of shooting smaller calibers because you will shoot them better and almost certainly will practice more. I bought a .223 and practiced a ton (1000+ rounds), which is about 900 rounds more than all combined rifle practice in the prior 30 years of my life. That fall, I killed an elk with that .223 even though everyone thought I was insane, because I loved that gun and shot it well. A mature cow elk went 8 yards and died in less than a minute. I put 4 shots into it with ease and though my shooting form and position was far from ideal, I still watched it all happen through the scope, which I had never done before.

I say this with the best intentions, having been in your shoes recently. You don’t know what you don’t know. Listen to the exo podcast with form and take it all in. You may need to listen a few times. I can almost guarantee you wouldn’t want the magnum for the elk or the grizzly in your scenario once you understand how significantly the recoil affects your hit rates and how irrelevant the larger wound it has the potential to create is.

Rokslide is a wealth of information. Continue asking good questions and keep an open mind when people respond, then you’ll be well on your way to maximizing your abilities as both a shooter and a hunter.

Podcast links for reference:

Hunt Backcountry Podcast 469 | Why Smaller Calibers May Be Better For Big Game Hunting — The Experience Project

This podcast will challenge decades of

exomtngear.com

Hunt Backcountry Podcast 470 | Why Smaller Calibers May Be Better For Big Game Hunting (Part 2) — The Experience Project

This is the second half of a conversation that explores why smaller rifle calibers may be better for big game hunting. This Hunt Backcountry Podcast episode explores how different types of bullets create different wound channels, the relationship between impact velocity and bullet...

exomtngear.com

Thanks for the info. I will check out those podcasts

 

[E.Shell]

Your cult point got a chuckle out of me. So true. But our great-grandfathers' generation got a lot of side-eye from their Boomer kids and grandkids for shooting things like .220 Swift and .22-250 at big game. And they slayed damn well.

^^ Truth ^^

When I was about 15 or 16 (50 years ago), my father bought me my first "deer rifle". He let me pick it out and gave me a budget. He suggested a Remington 788 in .30-30.

I decided to get the 788, but in .22-250 because I was also interested in shooting groundhogs. Although he eventually agreed, we had quite a bit of debate about it and he really wanted me to get a real deer caliber, not a varmint rifle. He was sure the .22-250 wouldn't kill a deer, but I showed him the energy figures and that the .22-250 had at least as much power as a .30-30.

I think I made the best choice and have killed dozens of deer with that rifle and with two other .22-250s I later had. Not only was it very effective on deer, but I shot almost everything with it, even had reduced loads for squirrels. After shooting groundhogs to 400 yards pretty routinely, deer at normal hunting ranges were a foregone conclusion.

Now, having drunk the kool-aid here, I have gone with the .223/5.56 and 77 TMKs for this season and have complete confidence in my rig. If my current .22-250 wasn't a heavy rifle, I'd just keep using that, but I'm getting too old to drag around a 10+ pound rifle.

 

[Marty]

@Formidilosus, fellow RokSliders:

• Are there statistically significant sample sized experiments that compare the same bullet type to caliber with respect to terminal performance? (ie. 6mm 108 ELDM compared to a 6.5mm ELDM compared to a 7mm 180 ELDM) Controls would include impact velocity, terminal media consistency, and angle of entry, etc. The purpose would be to understand what is being gained or given up by bullet caliber.
• Are there statistically significant sample sized experiments that compare recoil energy and velocity to probability of hit rates for centerfire rifles? I recall reading a military study that concluded recoil energy in excess of 8-12 ft/lbs yielded a significant reduction in hit rates. The purpose would be to understand where the tipping point of shooter performance degrades significantly enough to consider a lower recoil cartridge (just a deliver system for the desired terminal performance) or start adding recoil reducing features (if not already present) like a suppressor, properly shaped stock, weights, etc.
• Are there any recoil calculators for which you can plug in bullet weight, powder, and rifle weight and it would produce an estimated recoil energy and velocity value? I'm curious about adding weights to my chassis for training and competition and remove them for hunting.

Thanks!

 

[DagOtto]

@Formidilosus, fellow RokSliders:

• Are there statistically significant sample sized experiments that compare the same bullet type to caliber with respect to terminal performance? (ie. 6mm 108 ELDM compared to a 6.5mm ELDM compared to a 7mm 180 ELDM) Controls would include impact velocity, terminal media consistency, and angle of entry, etc. The purpose would be to understand what is being gained or given up by bullet caliber.
• Are there statistically significant sample sized experiments that compare recoil energy and velocity to probability of hit rates for centerfire rifles? I recall reading a military study that concluded recoil energy in excess of 8-12 ft/lbs yielded a significant reduction in hit rates. The purpose would be to understand where the tipping point of shooter performance degrades significantly enough to consider a lower recoil cartridge (just a deliver system for the desired terminal performance) or start adding recoil reducing features (if not already present) like a suppressor, properly shaped stock, weights, etc.
• Are there any recoil calculators for which you can plug in bullet weight, powder, and rifle weight and it would produce an estimated recoil energy and velocity value? I'm curious about adding weights to my chassis for training and competition and remove them for hunting.

Thanks!

Hi,

I've used this recoil calculator a lot.

ShootersCalculator.com | Recoil Calculator

An online calculator that calculates the recoil energy, impulse, and velocity of a firearm according to the firearm's weight, powder charge, bullet weight, and bullet muzzle velocity.

shooterscalculator.com

Keep in mind it does not introduce a reduction for recoil pad or muzzle brake. I do believe that a suppressor's added weight does roughly cover a suppressor's recoil reduction in this calculator but that is guess work on my part.

I've also attached backfire's recoil table. you can get this raw file at backfire.tv I've found this to be very helpful. Note that I have edited it to show all systems with 6.5 fp our less of recoil in yellow. This is the approximate line below which Form and others say recoil has minimum impact on shooters performance.

 

[bergie]

That fall, I killed an elk with that .223 even though everyone thought I was insane, because I loved that gun and shot it well. A mature cow elk went 8 yards and died in less than a minute. I put 4 shots into it with ease and though my shooting form and position was far from ideal, I still watched it all happen through the scope

I am not sure where I sit on this debate, I think both sides have valid points, but this contradictory statement to me is wild.

1. You love your .223 and you shoot it very well and you are convinced that the bullet you have selected will quickly and efficiently render the target incapacitated due to the large wound cavity that is 14-16" deep from a fragmenting bullet. - Obviously I have to believe this is true as you took it on an elk hunt.

2. You shot an elk FOUR times even though it only made it 8 yards and you spotted impact on all FOUR shots. - If true, how can this statement possibly follow the first?

If I trust my rifle (6.5 PRC, 147 ELD-M) which I do, I shoot once and if I spot my impact, which admittedly is not as often as I like (+1 point for small caliber folks). But for the sake of argument I do spot it and that sucker is 3" behind the shoulder, mid body in both lungs, the only thing I am thinking about is watching the animal tip over. The last thing I am thinking about is putting 3 more shots in it to potentially ruin more meat, which those match bullets certainly will do if I don't put it behind the shoulder where I want.

 

[Marty]

Hi,

I've used this recoil calculator a lot.

ShootersCalculator.com | Recoil Calculator

An online calculator that calculates the recoil energy, impulse, and velocity of a firearm according to the firearm's weight, powder charge, bullet weight, and bullet muzzle velocity.

shooterscalculator.com

Keep in mind it does not introduce a reduction for recoil pad or muzzle brake. I do believe that a suppressor's added weight does roughly cover a suppressor's recoil reduction in this calculator but that is guess work on my part.

I've also attached backfire's recoil table. you can get this raw file at backfire.tv I've found this to be very helpful. Note that I have edited it to show all systems with 6.5 fp our less of recoil in yellow. This is the approximate line below which Form and others say recoil has minimum impact on shooters performance.

Awesome, thanks for sharing! Great stuff.

 

[DagOtto]

Are there statistically significant sample sized experiments that compare the same bullet type to caliber with respect to terminal performance? (ie. 6mm 108 ELDM compared to a 6.5mm ELDM compared to a 7mm 180 ELDM) Controls would include impact velocity, terminal media consistency, and angle of entry, etc. The purpose would be to understand what is being gained or given up by bullet caliber.

It would be so incredible to have some real "statistically significant" data sets together to help to answer these questions with real information. But I haven't seen it. Granted, as other's have commented, it is difficult to document terminal ballistic performance on actual animals because of the large variance in environment, animal behaviour, and shooters' recall. But there are those who are working on it. Portland State University has an ongoing study which needs all of our data:

www.bit.ly/AmmoPerformance

I myself have started to compile a spreadsheet of the necropsy reports on this forum. I hope to complete that data entry project and publish the results sometime soon.

I hope that by gathering larger and larger sets of actual terminal ballistic field results trends will be identified.

I do give a lot of weight to those who have seen thousands of animals killed in the field. But the only two I know of who have shared their findings are Nathan Foster and Form. (Any others out there?) And although much of what they document and say is similar, (ie.. frangible/ soft bullets are a "must" at slower impact velocities and mono coppers wound less and need speed.) They do seemingly disagree on the value of larger caliber bullets on larger game.

Nathan's writings can be found here and I highly recommend his books:

Extensive Field-Tested Rifle & Cartridge Research - BallisticStudies.com

Expert rifle & cartridge research, carefully compiled through extensive field-testing & freely offered to the firearms community.

www.ballisticstudies.com

The only thing that is close to actual scientific data that I've been able to find is the online ballistic data from Hornady's law enforcement site. It has lots of test data for different bullets.

Attached you will find screen shots of various ELD-M bullets which shows an interesting trend. There is a clear tendency for the larger and heavier ELD-M bullets to penetrate more deeply and expand to create larger wound cavities.

225 gr. ELD-M in .308 @2888fps; 15" penetration and 8" dia. Max. Cavity
178 gr ELD-M in .308 @2894 fps; 14.25" penetration and 8.25" Max. Cavity
155 gr. ELD-M in .308 @2856 fps; 13.75" penetration and 6.00" Max Cavity
147 gr. ELD-M in 6.5mm @2646; 16" penetration and 5.5" Max Cavity

(Note the 6.5 bullet was traveling 200 fps +/- slower at impact which explains the deeper penetration. But the three .308's all impacted at very similar velocities.)

It "feels" logical to me that when comparing the same bullet: more weight, more diameter and more speed will equal more wound cavity and that at the same impact velocity a heavier, bigger bullet will also penetrate more deeply. But many on this site swear that isn't the case and I have less field experience then them so I'm left confused and deeply unsatisfied with the lack of data around an issue that would be easily "provable" in a properly orchestrated study. I've heard Form say that a bullet could be designed in .308 caliber that would produce massive soccer ball sized wounding, but have also seen him write that there is no significant difference in wounding created by .223 vs. .308 bullets. (not exact quotes, sorry.)

Bottom line is that I feel that this should be "settled" with real data for every hunting bullet on the market so we could move on to arguing about some other crazy hunting nuance. (or god forbid, by going to the range and shooting more!)

Also, I think it would be preliminary to look at this Hornady data and claim that it offers clear proof that there is an advantage in wounding and penetration by larger caliber and heavier bullets. Hornady doesn't state how many test shots were fired and I'm left with a sneaky suspicion it might have just been one of each bullet. To do this right, I think you'd need to do a larger sample size of each. And it would be important to test each at various impact velocities. The velocity of impact for all of these tests is pretty high at 2580-2730 which doesn't tell us how this bullet performs at lower velocities which is absolutely key for choosing a hunting bullet.

Interestingly, the comparison of the various CX mono copper bullets in the same publication does not yield the same trend of heavier, larger bullets creating more wounding.... Food for thought.

Before someone else points this out, let me state that it is very clear when one dives deeply into this that what really matters by a VERY large margin is bullet placement. In the hundreds of necropsy entries I have entered data for so far it is clear that if you hit an animal in the heart/lung complex with a well placed shot you are very likely to recover it within 40 yards of impact. No matter the caliber or projectile.

However, for reasons that others have pointed out: 1) debunking the lies that we've been fed 2) striving to be more ethical hunters 3) desiring exiting for blood tracking in heavy cover 4) balancing meat loss vs. quick killing and more,,, I will argue that this subject has real value and merit to pursue.

 

[ztc92]

I am not sure where I sit on this debate, I think both sides have valid points, but this contradictory statement to me is wild.

1. You love your .223 and you shoot it very well and you are convinced that the bullet you have selected will quickly and efficiently render the target incapacitated due to the large wound cavity that is 14-16" deep from a fragmenting bullet. - Obviously I have to believe this is true as you took it on an elk hunt.

2. You shot an elk FOUR times even though it only made it 8 yards and you spotted impact on all FOUR shots. - If true, how can this statement possibly follow the first?

If I trust my rifle (6.5 PRC, 147 ELD-M) which I do, I shoot once and if I spot my impact, which admittedly is not as often as I like (+1 point for small caliber folks). But for the sake of argument I do spot it and that sucker is 3" behind the shoulder, mid body in both lungs, the only thing I am thinking about is watching the animal tip over. The last thing I am thinking about is putting 3 more shots in it to potentially ruin more meat, which those match bullets certainly will do if I don't put it behind the shoulder where I want.

Appreciate the thought that went into this reply. A few counterpoints that may clarify things:

1) Some editorial choices were made there to get the point across that I wanted to, i.e. I firmly believe smaller calibers are better and I wish I’d used them sooner for all the reasons others have highlighted. That said, though I was truthful in my comment, it’s worth mentioning that I was not as practiced as I should have been for that shot opportunity. The shot was uphill as I sat in a bottom and I was awkwardly between seated and kneeling using a backpack as a front rest, which I had never practiced before. Though I did hit the elk with all 4 shots and did watch the animal react in the scope, I did not see the location of my impacts. If you read my prior comment again you’ll see I never mentioned seeing the impacts, though I understand my editorial choices could be a bit misleading.

2) Unlike larger calibers (and using high magnification, another bad habit I was raised with), with the .223 and 6x scope, I was able to get back on target very quickly. The person I was hunting with has significantly more hunting experience than me and was acting as spotter for me during this kill. Prior to the hunt, we had discussed that elk can go a long ways if wounded and so my hunting partner has a firm rule that you keep shooting until they’re down. As he spotted me shooting this elk he told me to keep shooting and I listened. From processing it after the kill, I know 2/4 hits were in the vitals and 1/4 was a bit further back in the area of the liver and 1/4 was a bad shot that hit the femur. I don’t know which shot was which but I know those 4 shots got the job done. I’m not proud of my shooting on that hunt and have since made a much more conscious effort to practice various positions and get better at seeing my impacts.

 

[DagOtto]

I've been working on trying to summarize the "small caliber for big game' argument into a quick "best practices" summary. Here is my first draft. I'd love feedback, edits and ideas of what is missing or shouldn't be in here:

The Best Practices For Affective and Humane Killing of North American Big Game
or
The Form Rokslide Way

1- The number one reason for wounding loss is that we as shooters suck.

2- To suck less, we need to practice weekly throughout the year with field and stress simulating drills.

3- A shooter's accuracy and ability to visually track an animal after the shot and apply an accurate follow-up shot is significantly worse as recoil increases.

4- Furthermore, a traditional high-recoil hunting rifle discourages hunters from practicing a lot which results in even poorer accuracy and field performance.

5-Shooters should practice and hunt with guns with less than 6.5 fp of recoil.

6- The quickest way to incapacitate and kill an animal is through a larger permanent wound channel with the ideal average diameter being 2 1/2" with diminishing returns (and more meat loss) when wound channels go beyond that.

7-Softer and more frangible bullets are much more effective at creating this size of wound channels than the typical bonded or mono-metal type bullets commonly sold as more effective on big game.

8- So-called tougher game animals do not pose a penetration challenge for softer frangible bullets

9-Given these facts-- the "best practice" for ethically and effectively killing game animals is to use smaller than typical calibers such as .223, .243/6mm and 6.5mm using a softer more frangible bullet than the typical recommendation. Examples of these bullets are Hornady ELD-X, ELD-M and Berger Elite Hunter.

10-The large majority of shooters should not consider ever taking a shot on an animal beyond 500 or 600 yards. There are various ways to test one's limits and to train to become better that one can explore, but wounding loss on animals goes up drastically beyond 400 yards and hunters typically overestimate their affective max shooting range by double to triple.

11-A hunting rifle should be built in a way that requires near zero maintenance to operate smoothly and to reliably hold zero. Tikka is a great low-cost option.

12-There are only a few scopes that are reliable enough to hold their zero through years of rigorous hunting use and these should be utilized to reduce zero shift and wounded or missed animals. Any scope from Nightforce or SWFA as well as many scopes from Trijicon and one scope from Maven all have passed rigorous testing. Scope power need not be any higher than 15 for hunting.

13-A new rifle should be dissasembled, degreased, and re-assembled using blue loctite, nail polish or paint pen as thread locker. If there is a lot of play between action and stock consider bedding. Action screws should be torqued to 55 or 60 fps, ring to rail screws should be torqued to 40 fps, and scope ring screws torqued to 30 fps.

14-A rifle should be zeroed by shooting a group of 10-15 rounds (cooling every 3-4 rounds) and then adjusted so the center of the resulting cone of fire is at the center of the target. A 10 round group of less than 1 MOA is quite rare and the difference between that rare gun and one that averages 1 to 1.5 MOA in field hunting affectiveness is nil.

15-Don't worry about cleaning your gun, ever.

 

[bergie]

Appreciate the thought that went into this reply. A few counterpoints that may clarify things:

1) Some editorial choices were made there to get the point across that I wanted to, i.e. I firmly believe smaller calibers are better and I wish I’d used them sooner for all the reasons others have highlighted. That said, though I was truthful in my comment, it’s worth mentioning that I was not as practiced as I should have been for that shot opportunity. The shot was uphill as I sat in a bottom and I was awkwardly between seated and kneeling using a backpack as a front rest, which I had never practiced before. Though I did hit the elk with all 4 shots and did watch the animal react in the scope, I did not see the location of my impacts. If you read my prior comment again you’ll see I never mentioned seeing the impacts, though I understand my editorial choices could be a bit misleading.

2) Unlike larger calibers (and using high magnification, another bad habit I was raised with), with the .223 and 6x scope, I was able to get back on target very quickly. The person I was hunting with has significantly more hunting experience than me and was acting as spotter for me during this kill. Prior to the hunt, we had discussed that elk can go a long ways if wounded and so my hunting partner has a firm rule that you keep shooting until they’re down. As he spotted me shooting this elk he told me to keep shooting and I listened. From processing it after the kill, I know 2/4 hits were in the vitals and 1/4 was a bit further back in the area of the liver and 1/4 was a bad shot that hit the femur. I don’t know which shot was which but I know those 4 shots got the job done. I’m not proud of my shooting on that hunt and have since made a much more conscious effort to practice various positions and get better at seeing my impacts.

Man...thank you for the clarification, and thank you for being honest. If I am being honest this was not the response I thought I would get. I was thinking your post was another post that simply wishes to prove that the .223 is good for taking large game, specific facts be damned, Again I don't know that I agree or disagree, but any time a point is trying to be made, intentionally or unintentionally, with misleading information my senses perk up. Also I am not saying all posts for small calibers / fragmentable bullets do any of the above, but I have read more than a few.

Knowing what I know now I would have done the same thing. I hate bloodshot meat as I process all my own critters, but I hate loosing an animal more.

I think we all can fall into the trap of what I think of as last experience reality, which basically means the last experience you had becomes the most important. I am guilty of this in this exact situation. The last deer a shot was about 10 days ago. Prone at 300 yards, I spotted my impact which was perfect mid body 4" behind the shoulder. I didn't even rack another round in the chamber as he ran off and died 20 seconds later. All I could think was how the hell could someone do the same thing I just did and decide to shoot it 3 more times? Turns out my last experience reality and your story are completely different which shouldn't be shocking.

 

[ztc92]

Man...thank you for the clarification, and thank you for being honest. If I am being honest this was not the response I thought I would get. I was thinking your post was another post that simply wishes to prove that the .223 is good for taking large game, specific facts be damned, Again I don't know that I agree or disagree, but any time a point is trying to be made, intentionally or unintentionally, with misleading information my senses perk up. Also I am not saying all posts for small calibers / fragmentable bullets do any of the above, but I have read more than a few.

Knowing what I know now I would have done the same thing. I hate bloodshot meat as I process all my own critters, but I hate loosing an animal more.

I think we all can fall into the trap of what I think of as last experience reality, which basically means the last experience you had becomes the most important. I am guilty of this in this exact situation. The last deer a shot was about 10 days ago. Prone at 300 yards, I spotted my impact which was perfect mid body 4" behind the shoulder. I didn't even rack another round in the chamber as he ran off and died 20 seconds later. All I could think was how the hell could someone do the same thing I just did and decide to shoot it 3 more times? Turns out my last experience reality and your story are completely different which shouldn't be shocking.

Yes of course, if we can’t be honest, than I’d argue these threads have little value. To your point about shooting an animal multiple times vs waiting for an animal to die after one good shot, I still don’t know where I land on that.

I grew up deer hunting in MN and my fellow hunters comfort with missed/wounded deer was a far cry from what I’m aspiring to today. I was taught to shoot once and then watch the deer run to help with tracking. I was young, recoil averse and using a lightweight 270 so I would come out of scope somewhat dazed and then try to watch the deer run with both eyes, never prepping for a second shot. It wasn’t uncommon for the simple “well that’s just hunting” excuse to be uttered when an animal wasn’t recovered. I often wonder if taking a second or even third shot may have led to more recovered animals. Of course with deer it gets tricky because they generally run and I don’t personally have the skill to make a good shot on a running deer. I’d argue most deer hunters would also struggle to make a good shot on a running deer. With elk, which generally move slowly at the shot from what I’ve seen/learned, a follow up shot is much more likely to hit the vitals.

Fast forward to now, and I was just home this fall to deer hunt and used my .223 again on a small buck. Unlike when I was young, I DID see the impact and knew the shot was good, right at the rear shoulder crease. I followed the deer in my scope as it ran, racked another round and was going to shoot again if he slowed down but he crashed within 50 yards, still in the field. As I said above, I’m not comfortable shooting at running animals so in this case I only shot once, but I would have taken a second shot if I’d had the opportunity and he wasn’t down yet.

Some other food for thought - we’ve all heard of animals that are hit well who still stay alive much longer than expected for the amount of damage done to vital tissue. This exact scenario happened to two friends/family members this fall while deer hunting. Both had a ton of blood in the chest cavity from lung/liver shots but the heart was not damaged and the deer required a finishing shot when found a little while later.

There are some on this forum who suggest that if the first shot is known to hit vitals, then second shot should be placed at base of the neck to anchor then and end it. I’m starting to think that may be the best balance of meat loss vs risk of losing an animal that runs off.

 

[bergie]

Some other food for thought - we’ve all heard of animals that are hit well who still stay alive much longer than expected for the amount of damage done to vital tissue. This exact scenario happened to two friends/family members this fall while deer hunting. Both had a ton of blood in the chest cavity from lung/liver shots but the heart was not damaged and the deer required a finishing shot when found a little while later.

There are some on this forum who suggest that if the first shot is known to hit vitals, then second shot should be placed at base of the neck to anchor then and end it. I’m starting to think that may be the best balance of meat loss vs risk of losing an animal that runs off.

Think what you want about the Ranch Fairy (he certainly is eccentric and has his own opinions), but he does offer some insight into the different types of lung shots. Before I watched some of his videos, I thought a double lung shot was a minute or less death sentence. Turns out the placement in the lungs is VERY important. My buddy shot a cow elk with a muzzy 3 blade a few years back. Shot looked maybe a little back and a little high but certainly not back far enough to clip the diaphragm so we let her sit for a half hour before taking up the blood trail. Probably an hour after the shot we came up to her, still alive. She jumped up and took off. We were dumbfounded. Waiting another 2 hours until dark and followed blood and found her about 40 yards from where she jumped up, stone dead. Shot hit the back 3rd of both lungs. I would have bet my house that she would have been dead within minutes, but that wasn't the case. Don't know the point I am trying to make here other than sometimes a follow-up is needed if sufficient time is not given to let the animal expire, even on a 'perfect double lung shot'.

As far as the second point, I used to be a neck shooter for follow-up shots but have since changed my stance. Maybe if its a cow or doe I might, but man there is a ton of meat on the neck of a rutted up buck or bull and I can't bring myself to waste it. If I need a follow-up I am aiming for the same place I did originally and if i get lucky I'll miss ribs on either side, further reducing any meat loss. Of course if a neck shot is all that is presented and I think the likely hood of the animal becoming unrecoverable is high, I will take any shot I can get.

I hate bloodshot enough that I have actually switched over most of my rifles to copper, but ran into issues getting copper to shoot well in my 6.5. I am not really a fan of the damage caused by the ELD-M but its hard to argue against it when it hits exactly where I want it to, and if I do my job there is little meat damage when poking through the middle of both lungs.

 

[Formidilosus]

@Formidilosus, fellow RokSliders:

• Are there statistically significant sample sized experiments that compare the same bullet type to caliber with respect to terminal performance? (ie. 6mm 108 ELDM compared to a 6.5mm ELDM compared to a 7mm 180 ELDM) Controls would include impact velocity, terminal media consistency, and angle of entry, etc. The purpose would be to understand what is being gained or given up by bullet caliber.

Not publicly that specific except for Hornady’s TAP, which isn’t supposed to be public.

• Are there statistically significant sample sized experiments that compare recoil energy and velocity to probability of hit rates for centerfire rifles? I recall reading a military study that concluded recoil energy in excess of 8-12 ft/lbs yielded a significant reduction in hit rates. The purpose would be to understand where the tipping point of shooter performance degrades significantly enough to consider a lower recoil cartridge (just a deliver system for the desired terminal performance) or start adding recoil reducing features (if not already present) like a suppressor, properly shaped stock, weights, etc.

The only publicly available ones are early 20th century US and British Army studies, and a US army study in the 60’s or 70’s that basically showed that groups open up as recoil is increased all the way to very high recoil levels.

• Are there any recoil calculators for which you can plug in bullet weight, powder, and rifle weight and it would produce an estimated recoil energy and velocity value? I'm curious about adding weights to my chassis for training and competition and remove them for hunting.

Thanks!

Google rifle recoil calculator.

 

[Formidilosus]

It would be so incredible to have some real "statistically significant" data sets together to help to answer these questions with real information. But I haven't seen it. Granted, as other's have commented, it is difficult to document terminal ballistic performance on actual animals because of the large variance in environment, animal behaviour, and shooters' recall. But there are those who are working on it. Portland State University has an ongoing study which needs all of our data:

www.bit.ly/AmmoPerformance

It’s going to be done. That study by questionnaire by Portland State is interesting, unfortunately it relies on hunters to correctly remember a lot of details.

I do give a lot of weight to those who have seen thousands of animals killed in the field. But the only two I know of who have shared their findings are Nathan Foster and Form. (Any others out there?) And although much of what they document and say is similar, (ie.. frangible/ soft bullets are a "must" at slower impact velocities and mono coppers wound less and need speed.) They do seemingly disagree on the value of larger caliber bullets on larger game.


Nathan's writings can be found here and I highly recommend his books:

Extensive Field-Tested Rifle & Cartridge Research - BallisticStudies.com

Expert rifle & cartridge research, carefully compiled through extensive field-testing & freely offered to the firearms community.

www.ballisticstudies.com

For general situational awareness- Nathan’s work is known by the terminal ballistics communities, and in in general is viewed with a heavy grain of salt as he is lacking in key basic terminal ballistics, and medically validated wounding mechanisms, and often attributes wounds or reactions to ideas or beliefs that have repeatedly been shown to be false. It doesn’t mean it’s all useless, but it does make it where ones has to really know what they are reading.

Attached you will find screen shots of various ELD-M bullets which shows an interesting trend. There is a clear tendency for the larger and heavier ELD-M bullets to penetrate more deeply and expand to create larger wound cavities.

225 gr. ELD-M in .308 @2888fps; 15" penetration and 8" dia. Max. Cavity
178 gr ELD-M in .308 @2894 fps; 14.25" penetration and 8.25" Max. Cavity
155 gr. ELD-M in .308 @2856 fps; 13.75" penetration and 6.00" Max Cavity
147 gr. ELD-M in 6.5mm @2646; 16" penetration and 5.5" Max Cavity

(Note the 6.5 bullet was traveling 200 fps +/- slower at impact which explains the deeper penetration. But the three .308's all impacted at very similar velocities.)

Remember those are max temporary stretch cavities- which may or may match the permanent crush cavity.

It "feels" logical to me that when comparing the same bullet: more weight, more diameter and more speed will equal more wound cavity and that at the same impact velocity a heavier, bigger bullet will also penetrate more deeply. But many on this site swear that isn't the case

It’s depends on bullet design. Just because one is bigger and heavier doesn’t mean it is designed for the same penetration depth or wound width. Yes, in general using ELD-M’s as an example- at the sam impact velocity the wound gets larger (not necessarily deeper) as you go up in caliber. However, the difference is less than most believe. It forms they dramatically different until the 178gr ELD-M and high impact velocities. As well, as the impact velocity gets lower, the differences become less in general.

and I have less field experience then them so I'm left confused and deeply unsatisfied with the lack of data around an issue that would be easily "provable" in a properly orchestrated study. I've heard Form say that a bullet could be designed in .308 caliber that would produce massive soccer ball sized wounding, but have also seen him write that there is no significant difference in wounding created by .223 vs. .308 bullets. (not exact quotes, sorry.)

That is based on commonly available bullets. There is and can be a difference of course, but again it’s not as dramatic as just believe unless using specific combinations- which very few do because people don’t want to lose the front half of the animal with every shot.
The real point is that wounds with good .224 bullets are already larger and creating more damage than 99% of people desire- going uo in bullet damage is NOT what people do.

 

[pods8 (Rugged Stitching)]

From there, you also get human factors cementing those cartridge ideas in place - the extreme money needed, with upper-class Brits leading the cultural charge of what "hunting Africa" entailed, combined with the romanticization of it all through hunting memoirs and fiction. That gets you to some form of culturally dictated..."One simply does not hunt the dangerous game of the dark continent without a proper large bore double-rifle, ol' boy. It would be quite unseemly."

BINGO. Did you read that african hunting forum thread where they talked about Ryan shooting the giraffe with the 6UM? One dude seriously said Ryan wasn't even dressed appropriately... I think it was wind gypsy that said they're basically playing dress up/LARPing with their african hunts and obviously you MUST have your big bore to be authentic.

 

[WRO]

If you need them drt, then stick with your magnum caliber, if you have no constraints shoot them with small calibers.

I haven’t seen one die in an acceptable time with 25 so far in our group in 6.5 or smaller. They all die, leave little to no blood trail and end up 50-100 yards from poi. Which is completely unacceptable for me. I’d archery hunt if I wanted to track.

 

[Jake Larsen]

If you need them drt, then stick with your magnum caliber, if you have no constraints shoot them with small calibers.

I haven’t seen one die in an acceptable time with 25 so far in our group in 6.5 or smaller. They all die, leave little to no blood trail and end up 50-100 yards from poi. Which is completely unacceptable for me. I’d archery hunt if I wanted to track.

Really? A lethally wounded animal can go 100 yards in a matter of a few seconds. If that’s not quick enough death for you, then “head” or “high shoulder” would be about the only acceptable shot placement.

Edit: not trying to be confrontational. Just noticing a lot of variance in what people find acceptable in terms of lethality.

Sent from my iPhone using Tapatalk

 

[WRO]

Really? A lethally wounded animal can go 100 yards in a matter of a few seconds. If that’s not quick enough death for you, then “head” or “high shoulder” would be about the only acceptable shot placement.

Edit: not trying to be confrontational. Just noticing a lot of variance in what people find acceptable in terms of lethality.

Sent from my iPhone using Tapatalk

It’s not, we hunt a lot of patchwork ground where they need to be drt as to not end up on the neighbors, in a fukin shithole, etc and in big herd situations many times you get one shot so wounding them to deaths isn’t an option.

The 6.5 is going back to being a deer rifle..