2600 fps "cut off point" for DRT behaviour?

[Bob Nelson 35Whelen]

Have used the 115 Nosler CT ST’s on several deer and one cow elk. They perform like a Nosler Ballistic Tip, which as I understand it they should. Same bullet with the coating? The cow elk was a 85 yard broadside shot through the ribs. Bullet did massive damage and surprisingly to me exited. Was an averaged sized one, 450-500 lbs. or so. Sample size of one...

It is a great deer bullet but I’d avoid shoulders as it will mess up some meat. I have used it on several deer and would not hesitate to do so again.

@TMac
Thanks for the feedback mate it is appreciated. What caliber did you use it in and what speed.
Bob

 

[TMac]

@TMac
Thanks for the feedback mate it is appreciated. What caliber did you use it in and what speed.
Bob

A 25-06 at 3,015 FPS average at the muzzle.

 

[Bob Nelson 35Whelen]

A 25-06 at 3,015 FPS average at the muzzle.

@TMac
I'm using my wildcat 25/303 Epps Newton improved and a muzzle velocity of 3,360fps so it may b shave differently, hopefully not to much tho.
Bob

My 25 loaded with a 100grain Barnes TTSX and 115 grain nosler combined technology silver tip.

 

[Tucketed]

Not to but in, elk archery I have seen two poor shots, one by myself and another a good friend. Both bulls hit through the liver and immediately the hit the ground flat out, two minutes later up on feet and slowly moving off. Both were recovered but I was amazed at what caused this. My guess was that the shock created an issue with blood flow to the brain?

 

[fourfive8]

NO idea about cut off point of velocity for DRT. DRT is a vernacular phrase that has crept into the hunting culture and means very little. Cut off point for effects of velocity is non-scientific by nature. Water (most liquids) are incompressible and kinetic energy is defined by 1/2 m(v)(v). The effects of the kinetic energy relationship among media, bullet and velocity seem like a continuum to me.

 

[Hogpatrol]

DRT, jumped a little, fell over and died where he stood. Never weighed everything 400 gr plus or minus, 305 fps. 238 lb. whitetail.

 

[TMac]

@TMac
I'm using my wildcat 25/303 Epps Newton improved and a muzzle velocity of 3,360fps so it may b shave differently, hopefully not to much tho.
Bob

If that’s 3,360fps with the 115 you may see even more “explosive results” up close than I’ve seen. I stopped using them as a number of new/inexperienced hunters used my 25-06 and ruined too much meat. It did kill very well however. Then I found it liked the 117gr Hornady InterLock even better, so went to those and 120gr Federal Fusions. All three were very quick killers on deer sized game, 150-350 pounds or so. It’s still my favorite deer rifle.

I went to having newer hunters use a 270 with Barnes 130gr TTSX’s, less meat damage and bullet fragments to worry about when newbs hit a shoulder. Try that 115 and let us know how you like it.

 

[colorado]

@bruce moulds
A thrown rock beats the 6mms.
Bob

That reminds me of what I told my friend when he bought a 9mm pistol (I shoot a 45). I told him if I just wanted to make someone angry, I'd insult them.

 

[Cam Moon]

I'm gonna be the odd man out and defend the 6mm. I used a Ruger M77 in 6mm Rem for YEARS with amazing results! Deer, Pronghorn, Elk, and Moose! Not only was I impressed with how well this little rifle worked, but it amazed my hunting buddies and anyone else who happened to see it. Now, I was shooting hand loads, and they were HOT, so perhaps factory loads wouldn't have been as impressive, but what I was using certainly was. I've read different threads where @One Day... has shared his experiences with his 257 Weatherby and it makes me want one! And I've chatted with @Bob Nelson 35Whelen about his .25 wildcat and I want it even more!!! I loved using my 6mm Rem, and it really showed what a great combination light and fast can be. These just do it at a whole nother level!
Oh, and Bob... I'm gonna go back and find where you first said that and give you a frown!

 

[Cam Moon]

@Madis Welcome to AH! I'm glad you have been impressed by your first impressions being on here. There truly is a great group of people here! Please feel free to ask any question that you would like to and please share with us your hunting experiences and knowledge you've acquired!

 

[Alaska Luke]

To answer an earlier question, Nathan views bigger bores (35 and up) as capable of shock kills at lower velocity. However he never guarantees it will happen, just that if your impact velocity is too low you will definitely NOT get an instant kill baring perfect shot placement or perhaps a super explosive bullet (which has its own issues of course). There are a lot of variables as Nathan says on his website. I view his rules as guidelines and parameters to work within not guarantees.

What I like about Nathan's website is it gives a framework to debate. You might disagree on something but saying "35 caliber bullets produce fast kills above 2200 fps" gives a consistent place to start talking and comparing.

I did witness 3 caribou kills with a 308 this year. All were fast enough but no instant kills. A friend used a hot loaded 7mm-08 and his caribou died almost instantly. Limited sample size but the extra velocity seemed to help. Similarly I shot a caribou at roughly 160 yards with a 358. The hit was good and the damage was massive but the caribou ran a bit. Later I finished off a wounded caribou at close range for an impact velocity of roughly 2400 fps (DRT territory for a big bore). Damage was similar but the caribou died much faster. So velocity seems to help.

 

[Bob Nelson 35Whelen]

I'm gonna be the odd man out and defend the 6mm. I used a Ruger M77 in 6mm Rem for YEARS with amazing results! Deer, Pronghorn, Elk, and Moose! Not only was I impressed with how well this little rifle worked, but it amazed my hunting buddies and anyone else who happened to see it. Now, I was shooting hand loads, and they were HOT, so perhaps factory loads wouldn't have been as impressive, but what I was using certainly was. I've read different threads where @One Day... has shared his experiences with his 257 Weatherby and it makes me want one! And I've chatted with @Bob Nelson 35Whelen about his .25 wildcat and I want it even more!!! I loved using my 6mm Rem, and it really showed what a great combination light and fast can be. These just do it at a whole nother level!
Oh, and Bob... I'm gonna go back and find where you first said that and give you a frown!

@Cam Moon
I don't mind a frown mate.
At least your 6mm is the 6mm Remington a far better cartridge than the Winchester 243.
You should give the 25 ought six a try you won't be disappointed.
Bob

 

[colorado]

I'm gonna be the odd man out and defend the 6mm. I used a Ruger M77 in 6mm Rem for YEARS with amazing results! Deer, Pronghorn, Elk, and Moose! Not only was I impressed with how well this little rifle worked, but it amazed my hunting buddies and anyone else who happened to see it. Now, I was shooting hand loads, and they were HOT, so perhaps factory loads wouldn't have been as impressive, but what I was using certainly was. I've read different threads where @One Day... has shared his experiences with his 257 Weatherby and it makes me want one! And I've chatted with @Bob Nelson 35Whelen about his .25 wildcat and I want it even more!!! I loved using my 6mm Rem, and it really showed what a great combination light and fast can be. These just do it at a whole nother level!
Oh, and Bob... I'm gonna go back and find where you first said that and give you a frown!

My first rifle was a Rem 700 BDL in 243. I hunted varmints with the Sierra 70g HPBT, big game with the 105 Speer Spitzer at 3000 fps. I handloaded with a Lee Loader. I killed many deer and two elk in Montana with it before I upgraded to a 270 Win. I heard too many stories about grizzlies sitting on hunter's elk as they came back to pack a second quarter out. Also, my outfitter wouldn't let me be an assistant guide with it, but said a 270 would be just fine. It was great on mule deer out to 400 yards, marginal on elk but both were one shot kills at 150 yards. I think the 270 is better on every front but recoil, but recoil for most is not an issue.

 

[mikecatt13]

I dont personally think you can put any science behind this as far as coming to a conclusion on animals in the field. I've seen less than ideal shots drop them in their tracks and perfect shots need hundreds of yards of tracking. Some species are know to be tougher than others

Particularly to the 2600fps theory...my 28 nosler has killed a whitetail, mule deer, and auodad. 162 Grain bullet going 3220 at the muzzle. All 3 "perfect" shots around or under 200 yards, only one went down RIGHT there. Granted, the other two went maybe 20 yards tops and the performance was quite impressive, youd think that 28N would be a good test to prove the 2600fps theory but while it works great, I dont see simple velocity even the main factor in being dead RIGHT there.

I've also seen several videos of hunters taking both .300WM and .375HH on a safari and arguably the .375HH dropping more game in their tracks, not a fast round. I'd wager that, aside from shot placement to the nervous system such as spine, energy coupled with bullet performance are more of a factor than velocity. Another example: I ran across a PH that said they prefer an accubond out of a .375HH vs something like an aframe for leopard. While you can find accounts of accubonds creating issues with tough plains game, the fact that they dont retain weight like an aframe means the energy dump into a light body, thin skinned leopard ends up in more dead at the bottom of the tree. Lends itself to the theory that it's not only even about velocity or energy itself but how its transferred as well

At the end of the day, my opinion is use a reliable bullet in an accurate gun that's sufficient for what your pursuing and put it in the right spot.

 

[Bob Nelson 35Whelen]

My first rifle was a Rem 700 BDL in 243. I hunted varmints with the Sierra 70g HPBT, big game with the 105 Speer Spitzer at 3000 fps. I handloaded with a Lee Loader. I killed many deer and two elk in Montana with it before I upgraded to a 270 Win. I heard too many stories about grizzlies sitting on hunter's elk as they came back to pack a second quarter out. Also, my outfitter wouldn't let me be an assistant guide with it, but said a 270 would be just fine. It was great on mule deer out to 400 yards, marginal on elk but both were one shot kills at 150 yards. I think the 270 is better on every front but recoil, but recoil for most is not an issue.

@colorado
Call me a sceptic as I have NEVER been able to get 3,000fps out of a,243 even with 87grain projectiles. The very best I could get with a 100 grain was 2,800 fps and the was with MAX LOADS of H4350 and H4831sc.
Those are chronoed velocities out of a 22inch barrel.
Bob

 

[One Day...]

I'm gonna be the odd man out and defend the 6mm. I used a Ruger M77 in 6mm Rem for YEARS with amazing results! Deer, Pronghorn, Elk, and Moose! Not only was I impressed with how well this little rifle worked, but it amazed my hunting buddies and anyone else who happened to see it. Now, I was shooting hand loads, and they were HOT, so perhaps factory loads wouldn't have been as impressive, but what I was using certainly was. I've read different threads where @One Day... has shared his experiences with his 257 Weatherby and it makes me want one! And I've chatted with @Bob Nelson 35Whelen about his .25 wildcat and I want it even more!!! I loved using my 6mm Rem, and it really showed what a great combination light and fast can be. These just do it at a whole nother level!
Oh, and Bob... I'm gonna go back and find where you first said that and give you a frown!

Oh yes! I am with you Cam Moon

I did not take my 6 mm Rem to Africa, but I have used it extensively in the French Alps. In those days (1970's and 1980's) laser rangefinders did not exist and we shot a lot closer. I would venture around 200 meters max in average. That made the Remington Express 100 Grain Core-Lokt load absolutely devastating. Private ownership of chronographs was also unthinkable in those days, so I have no idea if the advertised 3100 fps at the muzzle was a reality, but assuming it was reasonably close, that bullet was still going 2700 fps at 150 meters and 2600 at 200 yards. Plenty fast enough for DRT on small animals like Roe Buck (Chevreuil) or Chamois. If memory serves, the 100 gr Core Lokt all but disintegrated during expansion and it was an emphatic killer on these small animals at these distances. I never tried it on something bigger like Red Deer (Cerf) or Wild Boar (Sanglier) and I do not remember folks doing it, so I have no experience on the larger stuff.

I still have this 6 mm Rem and would not hesitate to use it on small and medium PG, and I would expect from it with modern bullets (80 gr TTSX) about the same performance as the .257 Wby out to 200 yards or so.

Mannlicher Schoenauer M72 in 6 mm Rem with swing mount Swarovski scope. The quintessential European mountain rifle of the 1970's.

As far as traumatic brain function disruption caused by a pressure wave carried through the circulatory system, I personally believe that military studies establish clearly that there is solid science behind it. Cleary there are a lot of variables, the main one being speed, but I have seen enough consistency in field results at 2600 fps and above, out to 200 yards with the 6 mm Rem and out to 300 yards with the .257 Wby, to be personally satisfied that the US Army researchers are correct...

As previously indicated, it is likely that brain incapacitation can also happen at lower impact speed than 2600 fps depending on the systolic pressure of the animal at the moment the bullet strikes. Apparently, when heart valves are opened in a favorable way during contraction of the left ventricle of the heart, at peak systolic pressure, when blood is shot out of the heart to the brain, even much slower calibers can produce hydrodynamic shock to the brain, through the aorta and carotid artery. As speed is reduced, frontal area (i.e. larger caliber) becomes more important to generate the same pressure wave. Conversely, at low diastolic pressure it takes a lot faster bullet (emphasis: faster; not: bigger or heavier) to produce the hydrodynamic shock to the brain.

 

[Bob Nelson 35Whelen]

Oh yes! I am with you Cam Moon

I did not take my 6 mm Rem to Africa, but I have used it extensively in the French Alps. In those days (1970's and 1980's) laser rangefinders did not exist and we shot a lot closer. I would venture around 200 meters max in average. That made the Remington Express 100 Grain Core-Lokt load absolutely devastating. Private ownership of chronographs was also unthinkable in those days, so I have no idea if the advertised 3100 fps at the muzzle was a reality, but assuming it was, that bullet was still going 2700 at 150 meters and 2600 at 200 yards. Plenty fast enough for DRT on small animals like Roe Buck (Chevreuil) or Chamois. If memory serves, the 100 gr Core Lokt all but disintegrated during expansion and it was an emphatic killer on these animals at these distances. I never tried it on something bigger like Red Deer (Cerf) or Wild Boar (Sanglier) and I do not remember folks doing it, so I have no experience on the larger stuff.

I still have this 6 mm Rem and would not hesitate using it an small and medium PG, and I would expect from it with modern bullets (80 gr TTSX) about the same performance as the .257 Wby out to 200 yards or so.

View attachment 377113
Mannlicher Schoenauer M72 in 6 mm Rem with swing mount Swarovski scope. The quintessential European mountain rifle of the 1970's

As far as traumatic brain function disruption caused by a pressure wave carried through the circulatory system, I personally believe that military studies establish clearly that there is solid science behind it. Cleary there are a lot of variables, the main one being speed, but I have seen enough consistency in field results at 2600 fps and above to be personally satisfied that the US Army researchers are correct...

@one-day
An 80grain ttsx out of a 6mm Remington may reach 3,200fps but my experience with reloading the 243 for friends with 87grain projectiles I wouldn't hold much hope of it getting much over 2,900fps with the ttsx.
This is a huge difference compared to the 257 Weatherby with 100grain Barnes TTSX.
In my own 25 I get a chronoed average of 3,670 fps with the 100grain Barnes TTSX. I think the extra 5 to 600 fps would make a big difference in killing power.
Just my 2cents worth
Bob

 

[One Day...]

@one-day
An 80grain ttsx out of a 6mm Remington may reach 3,200fps but my experience with reloading the 243 for friends with 87grain projectiles I wouldn't hold much hope of it getting much over 2,900fps with the ttsx.
This is a huge difference compared to the 257 Weatherby with 100grain Barnes TTSX.
In my own 25 I get a chronoed average of 3,670 fps with the 100grain Barnes TTSX. I think the extra 5 to 600 fps would make a big difference in killing power.
Just my 2cents worth
Bob

Agreed Bob

But if you read my above post carefully, you will notice that I state "out to 200 yards with the 6 mm Rem and out to 300 yards with the .257 Wby."

As we all agree, what triggers hydrodynamic shock is not muzzle speed but impact speed, and this is why I compare the 6 Rem 80 gr TTSX at 200 yards with the .257 Wby 100 gr TTSX at 300 yards, when both of them have essentially the same impact velocity

I am not sure that I fully agree re. the .243 Win. I agree that the 6 mm Rem is a faster cartridge because the 7x57 Mauser necked down to 6 mm has a larger powder capacity than the .308 necked down to 6 mm, but Barnes Vortex .243 Win factory ammo routinely reaches over 3200 fps with 80 gr pills, and that means that it too retains 2600+ fps out to 200 yards... The 6 mm Rem has an edge over the .243 Win, but it is typically only about 15 yards in MPBR...

 

[Bob Nelson 35Whelen]

Agreed Bob

But if you read my above post carefully, you will notice that I state "out to 200 yards with the 6 mm Rem and out to 300 yards with the .257 Wby."

As we all agree, what triggers hydrodynamic shock is not muzzle speed but impact speed, and this is why I compare the 6 Rem 80 gr TTSX at 200 yards with the .257 Wby 100 gr TTSX at 300 yards, when both of them have essentially the same impact velocity

I am not sure that I fully agree re. the .243 Win. I agree that the 6 mm Rem is a faster cartridge because the 7x57 Mauser necked down to 6 mm has a larger powder capacity that the .308 necked down to 6 mm, but .243 Win factory ammo routinely reaches 3300 fps with 80 gr pills, and that means that it too retains 2600 fps out to about 200+ yards... The 6 mm Rem has an edge over the .243 Win, but it is typically only about 15 yards in MPBR...

@one-day
I have chronoed 243 factory ammo from Winchester and federal using a 22inch barrel Tikka t3 lite and they were lucky if they could break 3,000 fps 87 grain projectiles.
I agree with your statement on the 6mm at 200 and the 257 at 300 and the 6mm Remington is definitely a class above the 243, it's a pitty it's not more popular. We have a gunwriter in OZ called Nick Harvey that thinks the 5mm AI is the ducks guts and right up there with the 240 Weatherby.
Bob

 

[Professor Mawla]

Velocity is quite important , Yes . But I am a big believer in heavy bullets at moderate velocities . Increased sectional density improves penetration . A heavier bullet also delivers greater shock to the central nervous system of an animal ( provided that the velocity is adequate ) .

For this reason , I prefer the following bullet weights :
- 100 grains for the .243 Winchester
- 175 grains for the 7x57 mm Mauser
- 220 grains for the .30-06 Springfield
- 250 grains for the .338 Winchester Magnum
- 500 grains for the .458 Winchester Magnum
- 600 grains for the .505 Gibbs