@doctari505 I would love to hear your thoughts about the use of NF CPS bullets in .4 class (404J, 416 Rigby, 416RM, 458WM, 458 Lott, 470NE, etc.) cartridges and .5 class (500J, 505 Gibbs, 500NE, etc.) as a primary choice for elephant hunting, including the possibility of frontal shots on big bulls. I'm not asking about choosing these bullets as insurance when hunting other game in ele areas, but as a primary choice for dedicated ele hunts...
Do these modern bullets (I guess the Woodleigh Hydrostatics operate on a similar concept to the NF CPS) open the possibility of elephant hunting in cartridges with adequate horsepower, or would you stick with the traditional advice of "solids only for elephant?" And if so, would they offer any theoretical advantages over a traditional solid, or one of the modern monolithic flat-nose solids such as the NF FPS, etc.?
600 grain .505 NF CPSs (at 2140 fps) were my carry load when I was at the Southern African Wildlife College which is situated within the greater Kruger National Park, where a 'self defence' situation from either a grumpy dagga boy or an ellie cow with PMS was always a possibility. This was my bullet of choice because it was more than adequate for such situations and I did have to shoot a lion-mauled dagga boy when it charged unprovoked three PH students and myself. I brained the bull at 5 paces and it dropped like a stone with the CPS passing through the brain, out the back of the scull down the side of the neck then through the spine at T2, through the right lung lobe and I recovered it at the back of the rumen. So I was able to both brain and spine the bull with one shot! What I found most interesting is that the hole into and out of the skull is exactly double caliber in side.
The Woodleigh Hydro is proving to be the best penetrator out there while creating the largest wound channels - this is why it is the first choice of my KNP game ranger friend who uses a .450 NE double for all his control work.
There is however a huge difference between 'hunting' and elephant and 'stopping' one.
In the former situation, when a frontal brain shot is needed for a quick, drop to the shot kill, the elephants head will be held up high as it looks down at you - this is because it needs this head position so as to be able focus on you with both eyes - to judge distsnce. If the shot is close, and it is a big bulls, the shot will need to be placed quite low down on the trunk to reach the brain. This can require up to 5 maybe even 6 feet of penetration for the bullet to reach the cranial cavity. Old Kynoch shaped bullets from even the popular big bore cartridges, especially the old cordite loaded ones never attained their advertised velocities and this, together with a poor bullet design meant some such shots never got to the brain. Modern-day flat nosed solids are much better penetrators.
So to answer your question in a long-winded way, I personally would be hesitant to take a frontal brain shot on an expensive, big bull trophy elephant when its head was up high with a CPS. From side-on it will work for sure but not every hunting situation guarantees such a shot.
In a charge situation the elephant will lower is head at the last minute. This changes the situation entirely because fron such a head position the penetration distance needed to reach the brain is considerably less - maybe as much as half of that when the head id held up high. So in such a situation a CPS will work. This is where I see a CPS in the chamber being a good choice when hunting other species.
The Swift Break Away Solid is a sort of blend between the two. Reports are that it penetrates well with a good sized wound channel but I have no real experience it. From the recovered ones I have seen, the 'rivet' the smallish cup the the nose contains and which creates it, is smaller than the 'cup' of the CPS.
For an expensive, trophy bull elephant hunt, regardless of caliber or cartridge I would be reluctant to 'experiment'.
The Woodleigh Hydro is now a well proven bullet giveing excellent penetration and larger than caliber permanent wound channels so this would be my bullet of choice - as heavy as it comes for that caliber.
My second choice would be the South African Dzombo - this bullet has a stellar reputation with the KNP rangers on all the pachyderms.
The NF FNS performs just as well as the Dzombo so it also comes highly recommended.
I have no exoerience with the FN CEB but I do not see why it would not perform equally as well.
Personally, I think the days of jacketed and lead core FMJs are over for expensive elephant hunts - why risk it when there are now so many better options out there.
I hope this is useful.