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Discussion Starter #61 (Edited)
He is concerned that the one bullet the rifle likes is inadequate as a long range elk round
He doesn't care for the Fusions? Everything I've read, said they were decent performers. I have a only little experience with the fusion. One goat and one hog, both were bang flops. It was definitely a bullet I was considering no matter what caliber we ended up with?
 

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Discussion Starter #62
Sounds like you need a Tikka in 7-08. Mate has one and I have a Ruger M77 in the same calibre.
No problem with our Bull Tahr and Red stag out to 450-500mm. They arent too much smaller than elk. I'll see if I can find some recent photos.

Tikkas shoot well out of the box. We shoots 162 ELD-X's, seem to do the business, admittedly hand loaded though. Not sure what the heaviest factory loads are out there.
A Tikka in 7-08 is on the short list. A Ruger would be too, if we can find one. A red stag bull is probably the same or only a little smaller than a cow elk. Encouraging the 7-08 performed well. Never shot tahr, but shot an audad this spring. Goats are tough.
 

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Discussion Starter #63 (Edited)
250 yards isn't long range.

It's not how much the bullet weights out of the barrel that determines penetration. It is how much the bullet weights after expansion which defines how much kinetic energy remains in the terminal phase. That is one advantage of the copper/monolithic bullets, even if the initial weight is less.
I never said I thought 250 yards was long range. It is the limit of what my wife feels comfortable hunting. I think we can get her within 50 yards. I feel pretty confident we can get her within 150 to 200 yards.

I think I have a, somewhat, decent understanding of the basic physics of bullet dynamics, but i am definitely no expert. I know lighter bullets produce lighter recoil. Lighter recoil is definitely something we're looking for in our choice of cartridge. Lighter recoil is the equal and opposite force of lighter forward momentum.

In the past, I've had disappointing results with copper bullets. Copper either failed to expand or sheard pedals. In my experience, lead/jacketed bullet performance is more forgiving then copper. I know copper bullet technology has greatly improved in the last 10-15 years. Xman, your data collection and fieldwork has got me to try monolithic copper again. Heck, it's one of the reasons I joined this site. I have a lot of respect for your work and your opinion. What is your hunting experience with copper at close range? I've already got a couple boxes of copper ammo in a few calibers to test on the next trip to TX on hogs. What's wrong with proof, keep the pictures coming!
 

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Federal Fusion 140gr. He has killed numerous whitetails,axis deer, hogs, cow nilgai and a sheep at 320 but is concerned not enough for elk at 400 yds.
 

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Booked a pack in trip in Shoshone for Oct 2021 for elk and outfitter suggested to be competent at 400-500 yd shots and use 30 cal or larger rifle.
 

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Booked a pack in trip in Shoshone for Oct 2021 for elk and outfitter suggested to be competent at 400-500 yd shots and use 30 cal or larger rifle.
Because he wants a humane kill...
More yards than he expects and bigger caliber than is needed.
He has my respect

Sent from my Pixel 3 using Tapatalk
 

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I never said I thought 250 yards was long range.
my apology, I should have used the new Reply button so the comment was then related to the long range comment.
 

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What is your hunting experience with copper at close range?
The majority of the .308 monolithic bullets are designed to handle the KE of the 300 WM so they have been very difficult to get the pedals to fail when expanding which, by default, limits expansion when shot from a .308 Win (expansion is directly proportional to KE with monolithic bullets). A few failures have occurred at 25 yards testing with 300 WM. My hunting buddy shot an elk head-on at 50 yards with a 165 GMX from his 300 WM. The bullet was recovered under the hide on the rump fully expanded with all its pedals. When testing his 150 Core-Lokts out of a 300 WM at 100 yards, the bullet disintegrates leaving no mass for expansion. When testing the .277 150 AccuBond Long Range in my .270, the bullet fragments away over 60% of its mass, even at 400 yards, leaving a little 55 grain mushroom to penetrate as far as a .223 55 grain bullet would. In both these lead-core bullets, the lead breaks down in flakes without significant mass to penetrate. Not all lead-core bullets react like this but these are examples of what happens when a lead-core bullet loses too much mass to retain KE for penetration.

When a monolithic bullet expands and loses its pedals, the petals have enough mass to continue penetrating, causing damage, and can be very lethal. The bullet's shank will continue to penetrate, often deeper than if the bullet retained its pedals because of less frontal area to transfer energy to the animal. The only monolithic bullets I have hunted with that have had enough KE for the bullet to fully expand and lose their pedals are .224 caliber. The two I've been hunting with are the 70 MKZ and 55 E-Tip. These were on coyotes with impressive results. I did a sequence of a coyote being shot with a 55 E-Tip at 60 yards (muzzle velocity of 3,400 fps). The image shows two columns of vapor/mist rising out of the entry and exit wounds just as the morning sun rise was washing out the scope. The impact knocked all the "stuffing" out the back-end, too.

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Here is a line up of GMX bullets recovered from terminal performance testing. The 3rd one was removed from a rib after over 30 inches of penetration in a cow elk that turned away as the trigger broke at 400 yards. It compared well with GMX bullets recovered from the bullet trap used in terminal performance testing except for it had more expansion. However, this was a 400 yard shot at 8500’ MSL which was 200 fps faster on impact than if the bullet was shot at sea level. This resulted in higher impact energy similar to a 300-yard impact which accounted for the for the larger expansion diameter. The elk took 4 steps and dropped.



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I've since switched over to Barnes LRX bullets. Barnes has worked on their tipped expansion cavity. Their TSX typically out expand the TTSX but the new expansion cavity in their LRX line does even better with greater than double-diameter expansion. I have not recovered an LRX, they always have been pass-throughs with an exit wound.

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Discussion Starter #72
Federal Fusion 140gr. He has killed numerous whitetails,axis deer, hogs, cow nilgai and a sheep at 320 but is concerned not enough for elk at 400 yds.
Nigai are some though critters, I've I've come close, but haven't shot one yet. I've seen them take a pounding.

Good luck on the Shoshone hunt! That 280 should work fine.
 

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Discussion Starter #73 (Edited)
Lead core bullets, by design, shed weight. It is a normal function of the hydrodynamic plastic flow. A lead and copper bullet at impact, and as it travels through flesh (gel, etc) a portion of the nose will flow, due to hydraulic pressure created by the energy of its momentum, and deform into the mushroom. A portion of the lead core flows off into the "flakes". As you point out, the flakes themselves lack enough mass to have their momentum carry through flesh with enough kinetic energy to be separate deadly missiles. However, the flakes do carry enough KE to widen a temporary and permanent wound channel. Centrifugal force created by rifling spin, is likely to contribute to this as well. If you've ever wondered why certain bullets, that look like there is almost nothing left, can leave such an impressive wound channel, it is this phenomenon at work. Sometimes there is little correlation in what a recovered bullet looks like, to the wound channel it left. The Acubond is a good example of this. This is not to be confused with fragmentation bullets, like Hornady SST. Incidentally the A-Max, V-Max and SST are all the same copper jacket and leadcore. It's the combination of tips and crimps that make them perform in different ways.

My preference for heavier bullets, comes from my experience, with a larger mass, there is more momentum to create the kinetic energy needed to work the bullet through more animal. How many times have we recovered bullets captured under the hide on the opposite side of an animal? While I am always very curious to examine the bullet, I get satisfaction when I find a large hole instead. I do not like chasing dead animals, but when I have to, I want an easy blood trail. From my observation, hydrodynamic flow works best when bullets lose 15% to 40% of their weight. I prefer something in the middle.

When I experimented with the original Barnes X and Fail-Safe copper bullets we saw success rates of about 60%. I would have preferred that 30% higher. We had a lot of bullets failed to expand, and when they did, pedals breaking off. The Fail-Safe shot fairly accurate, the Barnes X not so much. Part of that comes from not realizing just how far back from the lands copper bullets need to be loaded. Load data was sparse and usually cryptic. Copper bullets needed to be driven at high speed. High speed created issues with pressure spikes and excessive copper fouling of barrels. Chemicals used to remove the excessive copper fouling back then were harsh on steel barrels. Pedals would sheer on tough hides. The sheared pedals on the hide contributed very little extra wounding. Pedals wood sheer when striking bone, occasionally even ribs. However the copper slug then worked very well at smashing bone.

I believe copper bullets wood perform at a higher level if they had hydrodynamic flow. I know Barnes intentionally engineered their bullets to not have hydrodynamic flow, because of today's Hunter's obsession with weight retention. There are a few companies that have designed copper bullets with hydrodynamic flow in mind. Monolithic and copper alloy bullets do most of their work by cutting verses smashing their way through like a lead core bullet. This is evident in the excellent photographs provided by X-Men and Dfleury. To my observations, there is a distinct lack of bloodshot damage compared to lead core bullets. The wounds are similar to what would be expected to see from a broadhead.

It has been 15-20+ years since I last did any real experimentation with monolithic and copper alloy bullets. I realize the technology has evolved since then. I am seeing some impressive results. I believe copper bullets need a bit more engineering to reach the predictable lethality of a well-constructed lead core bullet.
 

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To my observations, there is a distinct lack of bloodshot damage compared to lead core bullets.
That bloodshot damage is lead fragments in your meat. I've watched elk brought in shot with 300 WM lead-core bullets that hit the shoulder and the processor just cuts the quarter off and throws it away. I'm a meat hunter which is one reason I hunt with copper bullets. The other reason is I too want to have an exit wound. Copper bullets retain their weight and penetrate more. Hides are elastic and act like a baseball glove. One of my hunting partners uses Accubonds for elk. He has more recovered Accubonds from elk than I could count (captured by the offside hide). I took a half-dozen and weight them. They averaged only 60% weight retention. I've only recovered 2 copper bullets and they were on elk after penetrating lengthwise through the body.
 

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It has been 15-20+ years since I last did any real experimentation with monolithic and copper alloy bullets. I realize the technology has evolved since then. I am seeing some impressive results. I believe copper bullets need a bit more engineering to reach the predictable lethality of a well-constructed lead core bullet.
The improvement in the last 5 years with copper bullets has been significant with no comparison to 15-20 years ago. The LRX has evolved to provide predictable lethality and so have most other copper bullets (but not all). The most lethal bullet I have used, copper or lead-core, is the CavityBack MKZ. Their .308 168 grain Tipped MKZ expands more than any supersonic bullet I've tested and the tri-star wound cavity it creates causes more hemorrhaging and blood loss than any other bullet in my experience. CavityBack hasn't made a tipped MKZ for the .270 yet or I would be using them. I've done more than 400 terminal performance tests on a variety of lead-core and copper bullets from .224 up to .308. I've only focused on posting 6.8mm SPC results because of this forum. I have tested as much or more with other calibers. Here is a compilation of copper bullet performance that I ppulled together this morning. Only the 55gr GMX is shown for .224. Showing all the .224 copper bullets would have turned the graph into a bowl of noodles and hidden the data that shows the effect of twist rate on copper bullet expansion. You need a 300 WM to reach the upper limits of the graph. A 300 BO with the proper twist rate was used for low-speed .308 bullet expansion. I needed the 300 BO because it became to time consuming and lgoistically challenging to test beyond 500 yards. It is interesting how closely the .277 and .308 data matches. I expect the 7mm bullets would fall right in-line also. The 129 LRX showed the most expansion in the .277 group. The graph does not include any MKZ expansion data - it would go off the right side of the chart.

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Discussion Starter #76
That bloodshot damage is lead fragments in your meat. I've watched elk brought in shot with 300 WM lead-core bullets that hit the shoulder and the processor just cuts the quarter off and throws it away. I'm a meat hunter which is one reason I hunt with copper bullets. The other reason is I too want to have an exit wound. Copper bullets retain their weight and penetrate more. Hides are elastic and act like a baseball glove. One of my hunting partners uses Accubonds for elk. He has more recovered Accubonds from elk than I could count (captured by the offside hide). I took a half-dozen and weight them. They averaged only 60% weight retention. I've only recovered 2 copper bullets and they were on elk after penetrating lengthwise through the body.
I apologize for my post being rambling or disjointed. I had a very long day at work and it was late at night as I wrote my response. I am in no way trying to be contrary, for the most part I agree completely with you, I am just trying to give an explanation as to why they are designed to preform in different ways.

Again, I apologize if my explanation was not clear. Hydrodynamic flow is responsible for the lead causing the bloodshot trauma to the meat. The leadcore bullets design cause bloodshot meat. Lead bullets, like copper, can be (some are) designed to have no hydrodynamic flow, resulting in less bloodshot meat. Accubonds are a premium bullet, their terminal performance is well-documented. They are designed to lose 40% of their total weight. Accubonds perform as well as they do, because they lose 40% of their weight. Sciroccos are designed to lose less of their total weight. Scirocco generally have a slightly smaller permanent wound channel than Accubonds, but it is not as common to recover a Scirocco. If you're hunting buddy stepped up to a higher weight accubond it is likely he would recover less bullets. Switching from 150 grain 180 grain accubond, assuming a 60% weight retention, the net result of almost 20% more mass. That 20% more mass is very likely to have the momentum to carry what's left through the hide. Speer had a line of bullets designed to expand but have little or no core loss due to hydrodynamic flow. I apologize for not remembering the name off the top of my head. It was a devastating bullet that left very little bloodshot meat. My brother had first-hand experience with them as very effective dangerous game stoppers, as well.

For decades manufacturers of copper bullets have been trying to get them to perform identical to leadcore. I think this is a mistake. There are cull/pest control hunters on this site alone, that have far more experience than I do. In my experience, when circumstances necessitated, copper bullets don't anchor animals, on average, as well as leadcore. As you point out, in the last 5 years or so, manufacturers are starting to design copper bullets based on the merits of copper and copper alloys. This is very encouraging. I have no direct personal experience with the latest in copper bullet design. I am intrigued by your examples and experience with the LXR and MKZ.

I understand most manufacturers do not have the pockets for expensive R&D. The level of precision engineering is truly impressive to, not just design these bullets, but mass-produce them. It is no exaggeration to say this engineering is far more precise than neurosurgery.

Living hide is elastic and flexible. Baseball mitts are flexible, but not so elastic. The end result is the same, catching projectiles. Leadcore and copper bullets have the same end result. Dead animals. How they perform the work is different.

I have several questions for you on your tests with the LXR and GMX. It will have to wait, I need to get back to work. Hopefully I can get home before 9:30 to night...
 

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If you're hunting buddy stepped up to a higher weight accubond it is likely he would recover less bullets.
He uses the 140 gr AccuBond is his light-weight 7mm Mag for hunting Bighorn Sheep and Mountain Goat in the Rockies. He uses the 160 gr in the 7mm Mag he uses for Elk which is their heaviest 7mm AccuBond.

I have found from my testing that manufacturers typically advertise a bullet line's expansion and minimum opening velocity based on their heaviest .308 bullet. As an example, the AccuBond Long Range advertises a 1300 fps min opening velocity. That is really for the heavy .308 bullets. For the .277 150 grain ABLR, the min opening velocity is 1500 fps which is an equivalent kinetic energy for the lighter .277 bullet.
 

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I am intrigued by your examples and experience with the LXR and MKZ.
When it comes to all copper you cant beat the cavity backs. The massive expansion helps overcome the shortfalls of most all copper bullets. All of my hunting and testing so far has been with the 120mkz out of either my 6.8 or 270msr but I do have tipped 168mkz's for my 308 loaded up that I plan to do some gel tests with. While you don't get as much blood shot meat as a lead bullets the temporary and permanent wound cavity I've seen in my gel tests exceeds most lead bullets. Here's some more pictures from my testing
 

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When it comes to all copper you cant beat the cavity backs. The massive expansion helps overcome the shortfalls of most all copper bullets. All of my hunting and testing so far has been with the 120mkz out of either my 6.8 or 270msr but I do have tipped 168mkz's for my 308 loaded up that I plan to do some gel tests with. While you don't get as much blood shot meat as a lead bullets the temporary and permanent wound cavity I've seen in my gel tests exceeds most lead bullets. Here's some more pictures from my testing
Question about the gel test, did the MKZ miss/glance the meat up front as i dont see any meat flying as we see with the sst? It looks like the bullets path either just missed it high or barely glanced it. Not questioning the performance of the bullet as many have commented on that elsewhere just wondering if that might be some of the difference in the temp cavity in the gel photo.



@Xman Any way you can share your data on other calibers? google doc. etc? Your thorough testing on 6.8 projectiles is the best i have seen and while this is a 6.8 forum there are plenty of us that shoot other rounds as well.
 

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sfs, I can develop some dedicated Threads for .224, .243, and .308 caliber bullets. Where would be the best location for them, General Hunting?
 
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