6.5 Hornady GMX bullet after 400yd cow elk shot

lifeisgoodsteve

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Hi All,

Thankfully had a great cow elk hunt a couple weeks ago, filled with seeing a good number of elk, getting in a great 2.5 mile stalk and coming home with some delicious elk meat.

When quartering and deboning we luckily found a copper prize of the Hornady GMX bullet lodged just below the surface of the skin in the front end of the opposite shoulder (was quartering away).

Bullet details:
Hornady Superformance
120 gr GMX (non-lead)
Muzzle Velocity 3050fps

Once shot the elk they all herded up and ran over the ridge, without any sign of one being wounded, so my mind started to wonder. A second later they all rounded back over the ridge to my heart's relief, as I scanned them to try to find one that's hurt. Without having to search for more than a second I saw one immediately pile up and fall, sliding down the steep snowy slope until it was stopped by a small evergreen, legs barely moving until they stopped less than a minute later.

So I'm guessing it ran about 60-75yds before falling, leaving a heck of a blood trail along the way. Just thought some might enjoy seeing what happened to the bullet and how it performed at 400yds., which is basically my max personal distance I'll shoot an animal with it.

Cheers,

Steve
 

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The Hornady GMX and the various Barnes bullets definitely perform well and get the job done!
 
I've been reluctant to try GMX because I've read reviews where they didn't expand well on longish shots with lower impact velocity. That's good to see. 👍

Thanks for sharing, and congrats on the elk!
 
Thanks guys. As a new hunter I wasn't sure what level of expansion is normal or optimal for ethical, quick kills. When I saw a photo of my buddy's 300 ultra mag bullet folded up like a mushroom all the way to the bottom at 400 yds, it got me wondering if I had enough rifle for those shots.

For reference, here's what Hornady has for that bullet at 400 yds (chart attached) to understand what it took for that level of expansion:
Velocity 2249
Energy 1347

Considering the very hotly debated topic of "what caliber is needed or best for shooting a ... ", it's probably a longshot (no pun intended) but is there any objective research/facts showing what actually causes the quick kill?

Is it the shock of impact therefore Energy which often mentioned (CO Parks and Wildlife recommends 1500min for elk)? Or is it the diameter of the bullet and penetration which causes the quick mortal wound? If so, then maybe Energy gives a general guide of how much expansion and penetration one might get. Make sense?

With this bit of actual evidence, or fact, I'm just curious to use it to better understand these items.
 

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I think DRT depends on two things. Shot placement and destruction by the bullet inside the animal. DRT I believes require's something to disrupt the central nervous system in some way. With a monolithic bullet I'd think you would have to hit the CNS. Unless maybe a petal was to break off and take it out. With a lead core bullet, piese's of lead and jacket material fly around making secondary projectiles that may not requite a precise placement for DRT. In either case the best route to DRT is precise placement!
 
Inter
My memory is not what it used to be but think he said it was an Accubond.
Interesting. I've recovered one Accubond out of dozens of animals killed out to 703 yards. I wouldn't use that one instance as a barometer to guage another cartridges effectiveness. mtmuley
 
Inter

Interesting. I've recovered one Accubond out of dozens of animals killed out to 703 yards. I wouldn't use that one instance as a barometer to guage another cartridges effectiveness. mtmuley

You're absolutely right and totally agree no blanket conclusions should be made.

I'm just ignorant as a new hunter so trying to educate myself with facts on "why" certain caliber/range/bullet choices are effective. Ultimately this will help feel confidence in my choices of what range to go out to for my existing 6.5 creedmoor and at what range/size animal it's wise to step up to a .300wsm rifle that's on my list as a next rifle. Then again, maybe just looking for justification for a new rifle. :)

By the way, in case anyone wants to dive deeper into this, I found an interesting article after my earlier post which goes into great detail:

Cheers
 
You're absolutely right and totally agree no blanket conclusions should be made.

I'm just ignorant as a new hunter so trying to educate myself with facts on "why" certain caliber/range/bullet choices are effective. Ultimately this will help feel confidence in my choices of what range to go out to for my existing 6.5 creedmoor and at what range/size animal it's wise to step up to a .300wsm rifle that's on my list as a next rifle. Then again, maybe just looking for justification for a new rifle. :)

By the way, in case anyone wants to dive deeper into this, I found an interesting article after my earlier post which goes into great detail:

Cheers
You need to call my bud at Hammer. He will talk bullets. Any kind. Honest info and he won't try to sell you. mtmuley
 
I've been reluctant to try GMX because I've read reviews where they didn't expand well on longish shots with lower impact velocity. That's good to see. 👍

Thanks for sharing, and congrats on the elk!
If you’re planning on using the GMX out to any range I’d go with the superformance line instead of the outfitter line or the full boar line of ammunition
 
Threshold of a dream. Hornady states that it takes about 2000 ft/sec to begin expansion. Not enough energy to punch through the cow though. Nice to see that it held together.
 
I would say that was pretty good performance, but any farther may have been a bit more problematic. At Creed velocities, the faster, the better, for sure. I think that any farther of a shot and the softer bullets would have been a better choice. BUT, 400 yards is a very realistic max, anyway. I don't think that you were under-gunned at all for that hunt. I have shot quite a few elk with 7 mags and 160 Partitions and some did not react any differently than yours did. They are big animals and unless you hit bone, they may go a bit before they realize that they are dead.
 
If you’re planning on using the GMX out to any range I’d go with the superformance line instead of the outfitter line or the full boar line of ammunition
Depends on what gun you are using, I was told by a Browning rep that the new 6.5 barrels were changed to shoot a heavier bullet. This was confirmed by some testing I did with a brand new xbolt 6.5 creedmoor. We shot the 120 GMX, 129 superformance and 143 ELDX. The 120 and 129 bullets would not hold a pattern, the 143 however would group less than 1/2'' at 100yds. This was done with the gun in a lead sled and allowing the barrel to cool between 3 shot groups.
 

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