Apex afterburner a few impact resistance results

fordy

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Gday
This is a reply I said I'd do from my last post on lrh on @frako21 thread

Sorry for the delay as had some major flooding to deal with in my local area

Hopefully this info is taken from a constructive position & will allow us all to learn a little bit more & what mark ( @mcdil ) does with it is solely upto him

My tests always cover as many possibilities from varying angles +low,med&high resistances with many velocity impacts that will potentially occur in the field for whom I do tests for

MY RESULTS: I'm not going to suger coat it as a failed shank is exactly that failed ! To me others may have a different view which is cool but please read on
I got other results that were more in line of what one would expect but the velocity window is way less than I assumed it would be by a big margin & so glad I tested these pills for a young fella prior to him heading out on a trip of a lifetime

The pill was the 135 afterburner shot from a 11 twist 300 rum @ approx 3810 MV ( I did get to 4053 but backed off as I have for a lot of my tests lately)
Pill rpm should be just shy of 250 k ( please check)

Velocity impacts ranged from 2730-3755

The 2 highest impacts ( resistance & velocity) 3605&3755 were complete & utter failures imo , the 3600 shank fractured 1AC6C813-19DB-48D4-AC00-DA9501C12E49.pngwhile I believe the 3750 shank disintegrated As I can't put anything else into the equation as all I could find was a 8 gr piece the tip & heaps of small fragments / flakes & no exits both had extremely shallow penertration not making it into the chest cavity ( both we're shoulder joint shots on the knuckle as I call it )

The next velocity impacts were around 3020&3080 which preformed better terminally & the shank held together ( resistance was medium) showing some interesting things to me 07928C56-E076-443C-879B-F028BB20DF59.jpegC3E7F252-BB26-42D3-9704-E9C9361C1565.jpegbut I'll see how far @Petey308 come before I open my mouth & please I'm not trying to be smart I'm seeing how far he has come to hopefully help him gain knowledge for his book also others please chime in if you've seen similar looking things

The impacts below 2900 I only found one petal & few fragments & terminal damage was extensive on low resistance

As always if I'm wrong on the way I've gone about things & anyone can relay the error in what /how I do things by all means tell me but please let's keep it civil & out of the gutter
cheers
Ps I've tried organising pictures but this muppet is having trouble & it will only allow me to add 10 so here's a few more I hope ABC6DCF2-AAD7-43C3-BE77-0CC5299F7B31.png255AA242-AA63-44BB-BD03-B950184DEDC3.pngDF7B3A70-54F3-4BFD-A7F5-44D44FCFE2BE.png15E90F2E-6811-4A9D-94D6-B6B37E07A43D.png4706230C-D90C-4DDB-9820-28A782563D0F.png4AF146AD-B2B2-4756-9C61-507C1C616B81.pngB730E3C5-7175-4388-8801-F8E04C6B94CF.png
 
Interesting results, and thanks for sharing.

Before diving too much into it, my initial thoughts and questions are as follows:

* Are you simply comparing your results with the Afterburner to your results with Hammers? If so, are you concluding any result that isn't the same is considered a failure? They're not designed exactly the same, they just both work on the principle that the petals are to be shed, leaving a flat-fronted shank behind to do the hydraulic work in regards to terminal performance. I believe the alloy content and perhaps other mechanics might vary between the two types and thus how they ultimately perform as designed will.

* I feel as though at the impact velocities you're putting that particular bullet at, and the centrifugal forces it's exerting, it's a bit too much for it. Impact velocities north of 3000fps is quite a bit to ask for most bullets. You stated that at lower impact velocities the damage was extensive and only found a petal and fragments, implying performance there was better, which would be what I'd expect and anticipate.

* Did you lose any animals in your testing? Did any run far?

* As I talk about often, sectional density needs to be factored in, even with monos. Yes, typically monos work best starting with a lower SD, but the 135gr .308" bullet is quite low, relatively speaking, at only .203, and when pushed at RUM velocities and at close ranges, it's just a lot to ask for how that particular bullet is constructed and designed to perform. It's going to come apart pretty much immediately and then there's not much left to work with. You should expect to see a lot of fracturing and pieces. Slowing down the impact velocity would slow down the rate of expansion and fracturing. As would lowering the RPMs (centrifugal forces). There is an upper limit to monos too, and that would vary by design and particular weight/caliber as well.


Again, I find your results interesting and useful, but I'm not ready to take them as conclusive based on the aforementioned points. In my opinion, it was one bullet, pushed to the upper limit (or perhaps beyond) and while I agree it sounds like it wasn't ideal performance, we did get the animal to examine, so not an entire failure. I'm glad you shared your results and I'm trying to keep an open mind, without bias, with it all.

My next test for you would be to try a heavier version from the same cartridge and see how it compares. I'd anticipate better overall performance as the SD will begin to better balance with the impact velocity and bullet design.

Just my initial thoughts,

Aaron.
 
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Very interesting. We've pushed them as hard as we can but haven't been able to demonstrate what you've been able to do at the extremes (our extremes were just not as severe as you've been able to conduct). Some of that work is even into dry, compacted leather from a RUM. Results were strikingly similar to those seen on the cattle. We haven't even bothered to post those results, because they're consistent with other testing.

It's always great to find the limits. Normally, most would prefer to have that happen in private testing, not on an open forum, but such is the beauty of the internet sometimes for everyone's knowledge. This is incredibly useful for us here too, even though we may not like seeing it.

Now the work you've done is the extreme of extremes, but at Apex, we want to ensure all our customers experience the best possible results in the field, at least for the things we can control, and as I've always mentioned, we want to provide full disclosure in our literature. I'd like to take a conversation with you offline to understand where the boundaries may be that you've observed. Maybe you don't have a handle on that just yet, or maybe you do, but we will adjust our performance window for the Afterburner on our literature to not exceed the velocities you've experienced that started to deconstruct the shank section when hitting large bone.
 
I'm always more interested in the minimum velocity results. As in, what is the lowest velocity that the bullet will stop performing as expected.

The majority of us arnt hitting animals at 3700 fps. It is good info to have as a manufacturer so they can label the limits. But I seriously doubt bullet failure at 3500-3800 fps is going to make anyone not want to use the bullets.

Now, the bullet not performing/opening up as expected at say 2100-2200 fps, would definitely affect the usefulness but I Havnt seen that claim anywhere.

I like the live animal tests!
 
Gday
This is a reply I said I'd do from my last post on lrh on @frako21 thread

Sorry for the delay as had some major flooding to deal with in my local area

Hopefully this info is taken from a constructive position & will allow us all to learn a little bit more & what mark ( @mcdil ) does with it is solely upto him

My tests always cover as many possibilities from varying angles +low,med&high resistances with many velocity impacts that will potentially occur in the field for whom I do tests for

MY RESULTS: I'm not going to suger coat it as a failed shank is exactly that failed ! To me others may have a different view which is cool but please read on
I got other results that were more in line of what one would expect but the velocity window is way less than I assumed it would be by a big margin & so glad I tested these pills for a young fella prior to him heading out on a trip of a lifetime

The pill was the 135 afterburner shot from a 11 twist 300 rum @ approx 3810 MV ( I did get to 4053 but backed off as I have for a lot of my tests lately)
Pill rpm should be just shy of 250 k ( please check)

Velocity impacts ranged from 2730-3755

The 2 highest impacts ( resistance & velocity) 3605&3755 were complete & utter failures imo , the 3600 shank fractured View attachment 402675while I believe the 3750 shank disintegrated As I can't put anything else into the equation as all I could find was a 8 gr piece the tip & heaps of small fragments / flakes & no exits both had extremely shallow penertration not making it into the chest cavity ( both we're shoulder joint shots on the knuckle as I call it )

The next velocity impacts were around 3020&3080 which preformed better terminally & the shank held together ( resistance was medium) showing some interesting things to me View attachment 402676View attachment 402677but I'll see how far @Petey308 come before I open my mouth & please I'm not trying to be smart I'm seeing how far he has come to hopefully help him gain knowledge for his book also others please chime in if you've seen similar looking things

The impacts below 2900 I only found one petal & few fragments & terminal damage was extensive on low resistance

As always if I'm wrong on the way I've gone about things & anyone can relay the error in what /how I do things by all means tell me but please let's keep it civil & out of the gutter
cheers
Ps I've tried organising pictures but this muppet is having trouble & it will only allow me to add 10 so here's a few more I hope View attachment 402658View attachment 402659View attachment 402662View attachment 402663View attachment 402669View attachment 402670View attachment 402671
It still looks like a great pill as long as you keep it on the velocity window where it won't fracture
 
I'm always more interested in the minimum velocity results. As in, what is the lowest velocity that the bullet will stop performing as expected.

The majority of us arnt hitting animals at 3700 fps. It is good info to have as a manufacturer so they can label the limits. But I seriously doubt bullet failure at 3500-3800 fps is going to make anyone not want to use the bullets.

Now, the bullet not performing/opening up as expected at say 2100-2200 fps, would definitely affect the usefulness but I Havnt seen that claim anywhere.

I like the live animal tests!
This. If we were on Len Backus' short range hunting forum, then 3700 fps impacts could possibly be very useful. However, if I intend to shoot game at sub 100 yards, I likely won't use a 300 rum, more likely something along the lines of a .308 win or similar. But, you never know when game may pop up, testing the extremes is still good for overall knowledge and appreciated, though possibly limited in practicality. The 153 afterburner would be more appropriate for a 300 rum, though it requires the 30 cal standard of 10 twist, so the 135 is an understandable decision if a 10 twist 300 rum or similar rifle is not available.

As stated, I am personally eager to see on game performance in the lower velocity ranges, for instance a 153 from a 30-06 on an animal at distance would be very interesting. I may likely have my son test a 6.5 variant in a smaller cartridge, on pronghorn/deer out to range, and see how it does. I like how mono's in general punch above their weight range and make smaller cartridges a little more effective.
 
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bullet testing takes a lot of time and effort, and anybody that does it should be commended for their work, but it has to be honest you need one medium for all velocities or one velocity for different medium. testing should start at 100yds not at 25yds like your high velocity test. (ran your start at 3810 and impact at 3755 to figure yardage)
years ago I tested some very popular 117 and 126 mono in a 270-338 rum imp at the same velocities as your high velocity loads and experienced the same results total designation but never called it a failure.
Do you have any test info on high velocity in low impact medium, that would be helpful to others.
 
I'm always more interested in the minimum velocity results. As in, what is the lowest velocity that the bullet will stop performing as expected.

The majority of us arnt hitting animals at 3700 fps. It is good info to have as a manufacturer so they can label the limits. But I seriously doubt bullet failure at 3500-3800 fps is going to make anyone not want to use the bullets.

Now, the bullet not performing/opening up as expected at say 2100-2200 fps, would definitely affect the usefulness but I Havnt seen that claim anywhere.

I like the live animal tests!
This. If we were on Len Backus' short range hunting forum, then 3700 fps impacts could possibly be very useful. However, if I intend to shoot game at sub 100 yards, I likely won't use a 300 rum, more likely something along the lines of a .308 win or similar. But, you never know when game may pop up, testing the extremes is still good for overall knowledge and appreciated, though possibly limited in practicality. The 153 afterburner would be more appropriate for a 300 rum, though it requires the 30 cal standard of 10 twist, so the 135 is an understandable decision if a 10 twist 300 rum or similar rifle is not available.

As stated, I am personally eager to see on game performance in the lower velocity ranges, for instance a 153 from a 30-06 on an animal at distance would be very ininteresting. I may likely have my son test a 6.5 variant in a smaller cartridge, on pronghorn/deer out to range, and see how it does. I like how mono's in general punch above their weight range and make smaller cartridges a little more effective.
Completely agree with you both. Looks like we may be looking at the limit for that particular bullet at the high end, but I agree for my typical applications, the low end limit is more of a factor and more applicable.

Either way, it's still good to know both limits. I just don't want this to be seen as a full conclusion on this particular bullets performance overall. I'll just take it for what it is.
 
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