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Forum Index > Precision long range hunting and shooting > 7mm Practical (and magnums)

7mm Practical (and magnums)

31 Jan 2016
@ 08:45 pm (GMT)

Nathan Foster

From an email:

Hi Nathan

I have recently purchased a 7mm practical which I am very happy with it is very accurate. I have been shooting the 162 A-max and after shooting goats the other day I have not been very impressed with the A-max.
For example a goat shot through the shoulder at around 200 yards had maybe up to a 8 inch hole/wound but did not die. It was as though the projectile exploded on the surface. There was a few others with also massive holes with huge meat damage. I would have been annoyed if this was something better eating like a deer rather than an old billy.

Have you tried the SST or the new ELD-X through your practical?
I was after an all round hunting projectile that would knock most N.Z game down out to around 800 yards. Could you give me any input on this please.

Look forward to hearing from you.
Thanks .....

Reply:

Hi ..., as I wrote in the Cartridges book and perhaps also in sections of the KB (see 7mm rem Mag), the A-Max can struggle to effect a fast kill at very close ranges. This can be more of a batch problem too, some batches are simply extremely soft. It's the 'why' bit that you are missing. When animals drop on the spot with chest shots- its not generally an instant kill but instead involves coma, then death from blood loss. The coma is caused by nervous trauma or what I call hydrostatic shock- a term many people misunderstand, generally this occurs above 2600fps but with a frangible bullet can also occur at lower velocities. The bullet strikes and sends out an electrical impulse through the nervous system to the brain. The brain is told that there is a massive problem, so massive that it must shut down and go into a full diagnostic. The animal dies thereafter. From our perspective, it is an instant kill. However, this process is dependent on matching the bullet weight to the animal weight but speed is also a factor. There is a low speed cut off point but also a high speed cut off point. Sometimes when you drive a bullet too fast, the surface tension of water becomes much harder and in this sense, the impulse is not transmitted to the nervous center and no injury is recorded. This is a bit like being cut with a knife that is so sharp, that you fail to notice the wound on your body until you see the blood. The animal fails to register the wound and so fails to go into coma and what we perceive as an "instant kill".

If you take a 140 or 162gr SST and drive these into game at 2900fps, the animals drop quickly and the wound is broad. But if you take the same bullets and drive them into game at 3200fps impact velocity, although the vitals may be destroyed, the animals can run a long way. This is also a reason to be cautious with regards to new ultra velocity magnum cartridge designs.

Anyway, the first thing you need to explore is whether the wounding was thorough in the area of the vitals. Forget meat damage for now and look at the actual internal organs. Did the bullet do its job. If the bullet did not reach the vitals, then the batch of projectiles is certainly far too soft (but ideal for long range work). In this instance, dual loading can be useful. Another method is to be more precise with shot placement at close ranges. If you know the bullet has limitations at close ranges, you can work around it and for example, aim tight behind the shoulder, aiming to miss bone. Then as you reach further out, you can aim to break bone.

You asked whether the SST is better / less meat damage. At close ranges, wounds are a good 2.5 to 3" in diameter however penetration is somewhat better. The 162gr SST is a very emphatic killer to 1600fps but meat damage is about the same as the A-Max. Keep in mind that the 7mm Practical is a potent round and that meat damage is par for the course and is also a function of fast killing. You could use a Nosler Partition and still see the same extent of wounding.

Wide wounding comes more into its own at long ranges. The new 175gr ELD-X has not arrived in NZ yet but I believe that this will be the solution to your somewhat common problem at close ranges. This 'should' be good to 1600fps and its high BC should ensure that it does not reach 1600fps until it is a long, long way away.

Also keep in mind that my book series, particularly the cartridges book explains things better than I can explain in one email. There are factors here that I have neglected to fully explain but the above will suffice if you are in a rush for a solution.

Replies

1
03 Feb 2016
@ 06:41 am (GMT)

Mike Davis

Re: 7mm Practical (and magnums)
yeah its the same old same old.......
Ive seen this written a heap of times as of late
Joe Bloggs asks if the A Max etc are good for all ranges
and some guys say 'Ive used it from 0-600 yards with no issues"
while others suggest dual loading to get AROUND possibility of close range blow up and then get poo hooed by the first lot
Nathan you arent the only one who shoots long range who has given these cautions..Greg Duley has done so on numerous occasions.
and its not a new thing either if you think about it...the .22 centre fires have ALWAYS had this issue as to some extent has the .243
they both have varmit/target projectiles DESIGNED to break up into tiny wee bits fast on impact or more solidly constructed projectiles that will hold together and drive in deeper, it is beyond me why people still keep making this same basic mistake.....its not like the warnings arent out there(or in here LOL)
03 Feb 2016
@ 04:56 pm (GMT)

Sebastian Shand

Re: 7mm Practical (and magnums)
I am currently loading 140grain amax for my 6.5swede and have not yet shot anything with them but my mate borrowed my rifle as he was interested in the caliber and wanted to try it out. He shot a good size young stag from approx 50 metres and thankfully with buckfever he missed the shoulder and the bullet tucked in behind the shoulder going clean thru the animal and passing thru the lungs and out the other side. It dead ran approx 100metres before dropping dead. I asked him to take photos and upon inspection the damage to internels was fairly minimal with very little bruising were the bullet had past thru lungs. Is this the amax at close range or is it the 6.5 at high speed not creating internal mayhem? I have shot a lot of game with federal fusion 140g factory ammo from wild cats up to monster red stags and damage was never extensive but everything always went down on the spot all shots generally under 200metres. Once pushed past there on goats 300 metres plus it appeared they hadn't been hit. I think from memory fusion ammo was running about 2550fps. Sorry hope this makes sense I'm tapping it out on my phone.
03 Feb 2016
@ 11:20 pm (GMT)

Nathan Foster

Re: 7mm Practical (and magnums)
Hi Sebastian. Will do my best to help- seeing the carcass would help a great deal more.

The first thing to understand is that the Swede has limited power.

In the 'old days' I had a several folk complain to me about the 140gr Interlock pencilling through game. This was when the Swede first became popular on mass in the west. Folk including some gun writers stated that the Interlock must therefore be designed for the .264 Win Mag. What folk failed to und4erstand was that they were using a mild velocity cartridge. If you downloaded the .270 by several hundred feet per second, the results would be the same. I tested the Interlock throughly and it never failed to mushroom. It opened fast (within the first half inch of penetration, did what it could, lost around 50% weight, then carried on until it ran out of energy.

With A-MAX / ELD, we can create a wider wound (as can be done with the GameKing at normal ranges) but there is only so much this cartridge can give. The same goes for extended ranges and we eventually run out of energy when using the 6.5 bore, sometimes in an unexpected manner (see cartridges book).

As for your example, again, it's hard for me to say so I have to guess. If the animal was large, then it was not so much a case of too much muzzle velocity (being a Swede) but more of a case of only so much potential. If a good deal of energy was lost during the initial stages of penetration, the 140gr bullet can only do so much before wounding narrows and the remainder of the bullet carries on as per the Interlock example. It sounds as though the impact velocity was certainly low enough to prevent full fragmentation (which would have occurred on heavy bone). At this point, you also have to understand that changing projectiles can only take you so far due to the nature of this cartridge.

So lets look at the Partition as an example. This soft up front but will penetrate well. But the same problem remains. If the animal is large and that energy (soft up front) is spent quickly, the wound can only be so wide. That said, the Partition retains high velocity throughout wounding which is I believe why this bullet performs so well in the Swede- it can utilize hydraulic forces for wounding so long as impact velocity remains high.

One recent bullet that is hard to pin into any category is the 142gr Nosler LRAB. This is a very strange bullet. Core bonding generally inhibits wide wounding at low velocities. To make a core bonded work well- drive it fast and don't shoot too long (Your fusion load was a good example). But in this unique instance the BC is so immensely high that it seems like the Swede is never going to lose velocity and that it might just keep going around the globe. The hollow point is wide and deep so energy transfer is assured. The downside of this bullet design is that it is not really designed for the extremes we might use it at. For example, it will shed a lot of weight in close so we have to be a bit careful / realistic in close if we want to hunt heavy animals. And as suggested, core bonding and low velocity don't go well together. But again we have this 'ultra' high BC and there is certainly a place for this particular bullet.

But- will it turn the Swede into a death ray? No. There comes a point where you reach the limits of a cartridge no matter what you try. Is the Swede good or bad? Well this comes down to the perspective of the individual shooter, local game weights and ranges etc.

If you get a chance, do try dual loading with the Partition. My take is- if you are unhappy with this bullet on game at ranges inside 250 yards with full power (2750fps) loads, then you need to change calibers because it is difficult to outdo this bullet. The same goes for extended range work with the 140gr A-MAX / ELD.
03 Feb 2016
@ 11:27 pm (GMT)

Warwick Marflitt

Re: 7mm Practical (and magnums)
Sebastian. Have a read about the 6.5 x 55 Swede in the knowledge base on here mate. The books are way better more details!
I have a Swede and following the Books information. I've reloaded 140 grain A-Max's and Partition bullets and taken 8 deer up close and longer.
To put it bluntly factory ammo is shit. Haven't tried Superformance as I only reload and it's a different rifle with hand loads
You have pretty much answered your own question. Poor shot placement even with the best bullet will be a fail or a messy event. Especially when close. I double load having a Partition on top of my A max so if one pop s up close and I have a good shot angle I have the load to do the job.
If I see a deer further out. I have plenty of time to make a cup of tea, range with the RF binoculars remove magazine, quietly slide out the Partition replace magazine with a loud metallic CLICK and I am A max ready for a long shot.
For those who get Buck fever! A great remedy is to go swimming with the sharks at the aquarium!
As with many of life's Situations. You need the right tool for the job and the skills to use it correctly and efficiently. With a calm clear relaxed mindset.
05 Feb 2016
@ 08:01 pm (GMT)

Sebastian Shand

Re: 7mm Practical (and magnums)
i'll dig up the photos and upload them, they aren't very detailed as my mate wasn't sure what to take photos of.

I've hunted with the swede for 3years now and even tho i hate being under gunned when hunting i am in love with it but i know to learn its limitations and use it accordingly. i think i will start duel loading like you say nathan as one bullet will not do everything. whats the best way of going about duel loading? is poi a problem between the to bullets?
what are your suggestions for shot placement if using the amax in close? i have read thru all of your books and the knowledge base and from what i gathered was to tuck it in behind the shoulder and avoid main bones? correct me if I'm wrong?
this might be a bonkers idea but could it be possible to duel load with amax 140g and for bush hunting just down load it so impact speed mimics using it at extended ranges? and mark the cases with vivid?

on the changing calibers note i use my 7x57 or 375 H&H if i know I'm going to be strictly bush/close range hunting and the swede has become more of a target/project rifle i tinker with and hone my reloading skills with.

my apologies for hijacking the thread


05 Feb 2016
@ 08:11 pm (GMT)

Sebastian Shand

Re: 7mm Practical (and magnums)


05 Feb 2016
@ 08:11 pm (GMT)

Sebastian Shand

Re: 7mm Practical (and magnums)
05 Feb 2016
@ 08:12 pm (GMT)

Sebastian Shand

Re: 7mm Practical (and magnums)
05 Feb 2016
@ 08:12 pm (GMT)

Sebastian Shand

Re: 7mm Practical (and magnums)
05 Feb 2016
@ 11:00 pm (GMT)

Nathan Foster

Re: 7mm Practical (and magnums)
Thats actually pretty good performance.

Large animal versus small caliber. The wound is a good 2.5" wide, the A-Max has done well. There was very little bone on the way in, yet it did open up. The internal wound was large but the vitals were equally large relative to the wounding potential of the Swede.

Yes, if using the A-Max in close, tuck it in tight behind the shoulder. I would not download the Swede.

Dual loading- work up a fast potent Partition load with an accuracy goal of 1 MOA, does not have to be half MOA. .7 to .9" at 100 would be ideal.

Check to see where the final POI is in relation to the A-Max loads but don't change sight settings. The A-Max will most likely shoot high due to its BC (unless harmonics say otherwise). It would be ideal if the Amax is set 3" high at 100 yards and the Partition shot say 2" high with some acceptable left right deviation.

Just keep in mind that the Partition will not be able to create a wider wound. You have pretty much hit your limit in killing potential with this cartridge- it is what it is. However, with the Partition, you can aim well forwards, break bone, destroy the automic plexus and drop the animal on the spot. Note that secondary wounding from bone fragments with this shot placement may increase the wound channel diameter. If you aim to the rear, results will be much the same as shown in your photos.

This shot placment / method with the Partition is a key point and is what I have tried to explain in the KB.

You have not hijacked this thread. You have instead enhanced it and taken it in a most useful direction, even if slightly different from the initial start point. In the Swede text I have tried to explain limits etc but through this forum and your example we can explore this much further. This information will be beneficial to the many other readers using the Swede and kin.

Do try dual loading with the 140gr Partition if you can, then break bone.


06 Feb 2016
@ 12:16 am (GMT)

Warwick Marflitt

Re: 7mm Practical (and magnums)
Quote:




Sebastian here's a link to my 6.5×55 Swede reloading work with pictures. Have a look and a read mate.

http://www.ballisticstudies.com/Resources/Discussion+Forums/x_forum/17/thread/6405.html
06 Feb 2016
@ 02:07 am (GMT)

Martin Taylor

Re: 7mm Practical (and magnums)
Going back to the Amax Magnum thing...

I'll happily state and back my 300win mag running the 208 Amax is more than capable from 0 say 850! Foxes, dogs, goats or light/heavy deer it's proven itself time and time again. Would back it further but yet to find the right conditions and a willing test subject with that combo.

Seen many Reds, Fallow & Sambar fall to that combo whilst stalking and is the only load myself and a few friends use after Nathan got us into it. No dual loading needed which is an added bonus, a true all rounder in my book.

06 Feb 2016
@ 02:41 am (GMT)

Nathan Foster

Re: 7mm Practical (and magnums)
And on that note, I have just re-uploaded the game killing section of the KB.

http://www.ballisticstudies.com/Knowledgebase/Effective+Game+Killing.html
06 Feb 2016
@ 03:17 am (GMT)

Sebastian Shand

Re: 7mm Practical (and magnums)
and this would explain why i always had dead on the spot performance with the fusion load as i was hitting further forward and breaking big bones on the way thru. it always amazed me when i opened them up how little damage had been done but they poleaxed on the spot.
i will order me some partitions and get back to the loading bench! in the mean time the 375 will have to take up the slack.


06 Feb 2016
@ 08:48 pm (GMT)

Nathan Foster

Re: 7mm Practical (and magnums)
Keep your camera handy please, whether 6.5 or .375.
10 Feb 2016
@ 04:35 am (GMT)

Jim Moseley

Re: 7mm Practical (and magnums)
I've been shooting the Amax in a 7 mag for many years. It's about precision shooting, which means an animal at close range is not shot thru heavy bone. Anything under 300 yds should be head, neck, or behind the shoulder. I've shot game from coyote to caribou, 80 yds to 1100 yds. The Amax will do the job as long as the shooter knows the dynamics and limitations of the bullet. Mike Davis had it right in the post above. It's like beating a dead horse :-) I think the Amax is the best long range bullet on the market.
10 Feb 2016
@ 05:37 am (GMT)

Mike Davis

Re: 7mm Practical (and magnums)
Just re-read the game killing bit...Nathan your shot placement with 7.62 x39mm or 30/30 could have been written just for me LOL and thinking about the deer we have dropped bang flop with the wee x39mm yip that eggzachary where they were hit...front of chest our sons first and my last were both in crease behind animals left shoulder exiting well forwards of right leg. had great hunt on Sunday with mate and Meg, bush stalking at its best,looked up and saw red spiker peering at me from 25-30yards put rifle to shoulder closed bolt put finger on trigger and crosshair on head and said "bang your dead" and then watched confused deer walk away (my freezer still full) mate spotted a hind 10 minutes later but couldnt tell if fawn at foot or not so she walked away too. its great being able to be calm with deer in your sights and think calmly....sure beats the first stag I shot many many years ago. first and fifth shots hit but middle 3 went "somewhere near it" lever action working like a full auto.I clearly remember thinking stuff this before AIMING the 5th lol
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