Scaling bullet performance

[Dr Ray]

As a thought only, note that, I wonder whether it would be useful for dangerous game bullets to be scaled as in penetration into media at say various distances.
The idea is for us to be able to have a good idea of what bullets do what at whatever velocities.
That way we could choose what to reload for say Cape buffalo or leopard which require completely different bullet characteristics.
Just seeking some comments especially after reading the numerous comments on the Hornady dangerous game bullets and their performance.

 

[fourfive8]

Excellent point. When I set out to test a particular bullet in my media, I take an educated guess as to what the likely distance will be for the shot on game. Obviously for dangerous game that distance will be anywhere for nearly point blank out to maybe 75 yards. Since I reload, I have the luxury of loading to an impact velocity equivalent to that best guess distance. Once I know the chronographed muzzle velocity of a particular hunting load, ready for the field, I use a ballistics program like JBM to estimate the velocity at any given distance. I then load my test load to that velocity as interpolated and checked by chronograph so that when shooting into my test media, the velocity is close to the velocity at that distance. For example I know that such and such a bullet and load has a muzzle vel of 2550 fps. I know that I want to test the performance of that bullet with an impact velocity expected at say 100 yards of 2275 based on the ballistics calculator. I put together a load with a velocity of about 2275 fps and test fire into the media (about 15 ft from muzzle). That way I know what to expect from that bullet at the 100 yard range… and so on. I've done this with all manner of big game bullets and ammo from 6.5 mm up to .458. Over time, the data (using necropsy inspections, field results and media test results) tend to model expected performance of any bullet through a range of expected impact velocities. I won't even waste time and resources with most common cup and core non-bonded bullets- they are pretty much all reliably unreliable for use on big game. What's the point when there are soooo many excellent alternatives available. These alternative have been around quite a while beginning in the 1960s with the Partition and progressing right up until the present. Likewise I'm not a "sniper", I am a hunter and choose to get as close as possible or reasonable for the shot. I have no interest in testing bullets at impact vels commensurate with long range sniping… IMO past 300 yards or so. I have not tested hunting bullets at the relatively low vels expected for impacts at really long range.

 

[PHOENIX PHIL]

Excellent point. When I set out to test a particular bullet in my media, I take an educated guess as to what the likely distance will be for the shot on game. Obviously for dangerous game that distance will be anywhere for nearly point blank out to maybe 75 yards. Since I reload, I have the luxury of loading to an impact velocity equivalent to that best guess distance. Once I know the chronographed muzzle velocity of a particular hunting load, ready for the field, I use a ballistics program like JBM to estimate the velocity at any given distance. I then load my test load to that velocity as interpolated and checked by chronograph so that when shooting into my test media, the velocity is close to the velocity at that distance. For example I know that such and such a bullet and load has a muzzle vel of 2550 fps. I know that I want to test the performance of that bullet with an impact velocity expected at say 100 yards of 2275 based on the ballistics calculator. I put together a load with a velocity of about 2275 fps and test fire into the media (about 15 ft from muzzle). That way I know what to expect from that bullet at the 100 yard range… and so on. I've done this with all manner of big game bullets and ammo from 6.5 mm up to .458. Over time, the data (using necropsy inspections, field results and media test results) tend to model expected performance of any bullet through a range of expected impact velocities. I won't even waste time and resources with most common cup and core non-bonded bullets- they are pretty much all reliably unreliable for use on big game. What's the point when there are soooo many excellent alternatives available. These alternative have been around quite a while beginning in the 1960s with the Partition and progressing right up until the present. Likewise I'm not a "sniper", I am a hunter and choose to get as close as possible or reasonable for the shot. I have no interest in testing bullets at impact vels commensurate with long range sniping… IMO past 300 yards or so. I have not tested hunting bullets at the relatively low vels expected for impacts at really long range.

Doing my best Tim Allen grunt right now....love it. I saw in the Hornady thread some of your results. Have you worked with any of the CEB bullets yet?

 

[Royal27]

Yes please!

 

[Dr Ray]

I truly believe that manufacturers need to undertake these projects. Fourfive8 obviously has done some really great research and I'm truly impressed about interpolating from the energy requirements at a given impact point back to the rifle.
I have had frangible bullets blow up on the surface as they were driven obviously too fast for the short distance.
Maybe manufacturers will undertake such in their research and this research should provide us with great in-depth knowledge applicable to the game.

 

[fourfive8]

I have not done any testing of the CEB… I assume the brass design with the break away petals?? I did watch a test of this bullet a few years ago and the results claimed by CEB matched the independent tests I saw- very reliable, deep, straight line penetration. There are so many new designs out there right now that could be tested, it would be a major undertaking to do justice to the project. I the past few years, I think both GS and Woodleigh have done some very good research into terminal ballistics of some of their designs. In many instances these results seem to translate well to other similar designs of various other manufacturers.

 

[PHOENIX PHIL]

I have not done any testing of the CEB… I assume the brass design with the break away petals?? I did watch a test of this bullet a few years ago and the results claimed by CEB matched the independent tests I saw- very reliable, deep, straight line penetration. There are so many new designs out there right now that could be tested, it would be a major undertaking to do justice to the project. I the past few years, I think both GS and Woodleigh have done some very good research into terminal ballistics of some of their designs. In many instances these results seem to translate well to other similar designs of various other manufacturers.

Were the results you saw from Michael McCourry? This is a no doubt expensive undertaking and also quite time consuming. If you have the itch to try some 420gr .458's, the brass ones with the breakaway petals, I'll pony up a few boxes. That is presuming you are in the U.S. of course. Not sure I could ship them out of the country.

 

[fourfive8]

Were the results you saw from Michael McCourry? This is a no doubt expensive undertaking and also quite time consuming. If you have the itch to try some 420gr .458's, the brass ones with the breakaway petals, I'll pony up a few boxes. That is presuming you are in the U.S. of course. Not sure I could ship them out of the country.

No problem. I have access to various bullets including the CEBs. I'd be glad to test the 458 420 HP Raptors at a couple of different impact vels. My 45 cal platform is a 450 Watts. Easy to duplicate everything from mild 458 WM up through hot 458 Lott. And yes, I believe the tests I saw were done by the fellow you mentioned. It is not difficult to do, just time consuming. Give me some time and I'll post results here. I'll do a couple of tests of the 458 420 gr HP Raptor- one simulating an average 458 WM hunting load at 40 yard equiv. impact velocity and one simulating an average 458 Lott hunting load at 40 yard equiv. impact velocity.

 

[Shawn.54]

I like this idea is there a way to come up with a test medium that we could all replicate so that we could try our own tests an know that we are comparing apples to apples. I love to shoot and recover bullets.

 

[fourfive8]

Apples to apples…. good point but difficult to achieve unless standard specs are specific and consistent. I think a ballistic gel held to a universal formula would come close. It works great for wowie and video purposes but may fall short for severe testing as demanded for proper appraisal of a DG bullet. Another easy test is using a horizontal stack of water filled plastic "milk" jugs. I think the early tests I saw for the Cutting Edge Raptor bullet and also by one of the companies making specialty type large bore ammo, utilized wet paper as the basic media. I believe, the media used for the CEB test was called "wet pack". But there is wet paper and there is wet paper. Wet, loosely bundled newsprint is very different from wet bundled gloss paper catalogs which is very different from wet bundled phone books which is very different from wet bundled hard cardboard… and so on. For base media, I use phone books bundled into 4-6 inch wafers with nylon string then soaked in water for apporx. 12 hours to ensure complete saturation. Between the first and second wafer I place a 2 to 3 inch thick hardwood block set at an angle to simulate bone. This media stack is held horizontally in place by a plywood trough about 3 1/2 feet long. The shot (axis of travel) is fired as close as possible to the center of the first wafer and as close as possible to the axis of all the wafers in the horizontal stack. After the shot, each wafer is opened and leafed through to determine effect and recover bullet parts. A new stack of media has to be assembled after each test so tests are as consistent as possible. Some fragile bullets may only spoil a wafer or two. Some well designed solids may penetrate and spoil many bundled wafers. The results are measured using a tape and notes recorded. The test media I use as described does test a bullet. But the tests are done consistently so they are fair. They will reveal design/construction weaknesses. It's much easier to use something like water filled jugs but I think the wet bundled phone book paper with simulated "bone" comes closer to a real test. Loading ammo regulated to proper impact velocity, assembling enough phone books, 12 hr water soak, range set up, test shooting, inspecting/measuring/recording then re-assembling for the next shot…. all very time consuming.

I just watched the latest CEB video on their Raptor tests. It uses slow mo in clear gel so has a marketing wow factor but it may not stress a bullet enough to cover all the possibilities for something like a dangerous game bullet… like oblique angle of penetration of bone, wet/dense rumen contents, alternation layers of tough tissue-bone-soft tissue, etc…

Long ago I started using the above bundled wet phone book/hardwood media so need to stay with it so I am comparing apples to apples within my test universe and can then compare and extrapolate results that are observed against actual field observations and recovered hunting bullets.

 

[Shawn.54]

The phone book sounds great with hard wood as bone that would give a fair test.
In my area the phone books were rarely 1.5" thick and now that cell phones are everywhere the books are under 1/2" and shrinking I would have to get the whole county to save me their books to take one shot. The local school my be getting rid of some old text books.

 

[Royal27]

The phone book sounds great with hard wood as bone that would give a fair test.
In my area the phone books were rarely 1.5" thick and now that cell phones are everywhere the books are under 1/2" and shrinking I would have to get the whole county to save me their books to take one shot. The local school my be getting rid of some old text books.

The future of test media....

 

[stug]

I read somewhere, longrangehunting I think where a guy used a kitty litter type material soaked in water in a box. He had plastic inserts at various places to easily see how far the projectile went and make it easier to find.
The funniest test I saw was a pile of sausages, steak and chops, wrapped together and shot at 100yds. I tried to find the video of it but can't, was a few years ago now.

 

[Rule 303]

Dr Ray, that is a good idea.

fourfive8 that method is very time consuming and to my thinking a far better way for reality than the ballistic jell.

 

[Dr Ray]

Dr Ray, that is a good idea.

fourfive8 that method is very time consuming and to my thinking a far better way for reality than the ballistic jell.

Thanks. I have had some very bad experiences with bullets being either too soft or too hard and causing flesh wounds or in having the drilled through animal run a long distance.

 

[fourfive8]

Were the results you saw from Michael McCourry? This is a no doubt expensive undertaking and also quite time consuming. If you have the itch to try some 420gr .458's, the brass ones with the breakaway petals, I'll pony up a few boxes. That is presuming you are in the U.S. of course. Not sure I could ship them out of the country.

OK. Set aside enough time, gathered enough media material and got ahold of some 420 gr 458 Safari Raptor bullets- a turned brass, 6 petal hollow point. Using a chronograph, I found a load to approximate a 40 yd impact vel somewhere between 458 Win and 458 Lott ballistics... right at 2000 fps for media impact vel. These bullets have a fairly large hp meplat so the BC is low at about .19. Since they are most assuredly a DG bullet, no worries for the intended ranges from point blank out to maybe 100 yds.

Media was completely water saturated phone books (10 hrs), bundled into approx 4" thick wafers. A 2 1/4" hardwood block was set between 1st and 2nd wafer to simulate bone. Test bullet was fired center of mass and parallel to axis of media stack. Petals began to visibly separate at approx the 1" penetration mark. A normal "permanent" channel cavity, elongated sphere in shape, extended from approx the 2" depth mark out to the interface with the hardwood block. The largest diameter of the spherical channel was approx 3" at the 3 1/2" depth mark. The penetration tracks of all 6 petals radiated outward from the track of the main bullet shank in a symmetrical pattern. I recovered 3 of the 6 petals. Most of the petals penetrated fully past the 4" mark and three were lost beyond the edges of the media boundary. The bullet shank penetrated in a straight line to a depth of 21.5" and was found nose end forward at that depth. The weight of the recovered shank was 335 gr. Petals (of the 3 found) averaged 14 gr ea. So 335 gr plus 84 gr (6x14) = 419 gr. I noted no shards of brass in the media along the bullet track or petal tracks other than a few fine brass "dust" particles.

The test results for this design, The CEB HP Safari Raptor, were consistent with and agree with similar tests done by CEB and others- both into ballistic gel and wet pack (paper). The performance of this bullet is very similar to the results I've found for the comparable North Fork Cup Point Solid bullet. The bullet behavior and bullet path channels are very similar as is the depth of penetration into the same media. The major difference noted was the Raptor bullet produced a slightly larger spherical channel than the NF Cup Point Solid- from the 2" to 4" mark.

This appears to be a very predictable type design and I would expect excellent performance for use as a dangerous game, "controlled expanding" bullet. In some ways the mechanics of its behavior are not unlike that of the Nosler Partition which also "sheds" its nose during travel through media. The main difference being the individual petal projectiles of the Raptor vs the halo ring of very small abraded particles of core and jacket of the Partition. I would think the Raptor to be ultimately tougher than the Partition if exposed to the most extreme terminal ballistic forces. The Partition base shank can shuck its core (rare but possible) while the solid brass Raptor base shank can't by design.

 

[fourfive8]

To put all that into some perspective, using the same test media- a good bonded or monolithic expanding (TSX) 180-225 gr 30 or 338 cal bullet with a 100 yard impact vel out of average calibers, will penetrate about 12-14". Many times this type caliber and bullet will penetrate completely through plains game up to wildebeest size. A similar 416 400 gr expanding bullet like the A Frame or TSX at a slightly lower impact velocity will penetrate just a little deeper at 14-16". A 458 450-480-500 gr flat point monolithic solid at a slightly lower impact vel yet will penetrate 22-26". That same 458 caliber flat point solid with that same impact vel will likely penetrate a Cape buffalo length wise. The 458 cal 480 gr DGX test using this media, as reported in the other thread, showed a penetration of the base section of the jacket at about 9" and the bottom half of the separated core at about 12".

Back in the days of transition between black and smokeless powder when ammo companies were scrambling trying to figure out suitable bullets for big game WDM Bell had the opportunity to try most every combination available. He became convinced early on and with the luxury of experience through many failures, that shot placement and penetration trumped all the impressive wowies of explosive bullet behavior. We are still seeing that debate today, over a hundred years later, about frangible, non-bonded cup and core bullets versus much tougher, penetrating bullets at relatively high impact velocities.

 

[fourfive8]

Diagram of 420 gr 458 CEB Safari Raptor test

 

[Ray B]

Bills Steigers, the late maker of Bitterroot Bullets preferred five gallon steel cans such as farm chemicals and oils are sold in, filled with water and laid on their side so that the bullet impacted the bottom and travelled to the top. If the bullet made it through the first can, there was another behind it. the cans were about fifteen inches in diameter so could be placed at various ranges so that actual impact velocities and rotation could be tested. While it didn't mirror game bone or tissue, it did provide a constant test medium to that one bullets performance could be compared to another.

 

[PHOENIX PHIL]

Nice work @fourfive8! My one concern with the Raptor style bullets is on quartering away shots. I wouldn't want to shoot something big and dangerous on a hard quartering away shot that would result in shooting thru the paunch first to get into the heart/lungs no matter what bullet. But given that we can't control everything and mistakes may happen, I wonder if heavier NF or A-Frame that retains more weight wouldn't give better results in that scenario.

I do know this, @PaulT, when he was guiding for those Australian buff, saw a lot of bulls taken with the CEB Raptors and couldn't speak more highly of their performance.