I expect that a rimmed case will provide more peace of mind than a rimless one during the situations where the Double Rifle has the advantage over a bolt rifle. It is why rimless shotgun shells are not on the market today.

That old BOOM-BOOM! versus BOOM-rack the bolt-BOOM scenario.

Don't tell me you are getting DR fever...?

regards,

Rich

quote:

Of course it is also not written that one must use one over the other, that still, as we speak, remains free choice! My choice is flanged cartridges in a double rifle, others may do as it suits them!

Amen!

Will,

What will the .470 do for you? - It definitely will make you change your signature tag line!

At the risk of being seen as a perpetual nay-sayer, I ask you to consider the following: Every action has a certain amount of "give". The action springs slightly open at the highest moment of pressure, then springs back when the pressure subsides. A tapered case will "wedge" into the chamber where a straight walled case will not. A belted .375 H&H, with pressures intended for a bolt actioned rifle and its powerful primary extraction system, is a greater challange for the relatively weak extraction system of a double rifle than a straight sided case. A .375 H&H Flanged probably would not have had the same problem, since that cartridge is loaded to lower pressure levels than its belted, rimless version.

What would be the typical cost to convert this gun and have it regulated for a 450 X 3.25?

It is obvious that a double rifle action is very weak compared to a bolt rifle. The higher the pressure of the cartridge the sooner it will come off face.

465H&H

quote:

Originally posted by xausa:
At the risk of being seen as a perpetual nay-sayer, I ask you to consider the following: Every action has a certain amount of "give". The action springs slightly open at the highest moment of pressure, then springs back when the pressure subsides. A tapered case will "wedge" into the chamber where a straight walled case will not. A belted .375 H&H, with pressures intended for a bolt actioned rifle and its powerful primary extraction system, is a greater challange for the relatively weak extraction system of a double rifle than a straight sided case. A .375 H&H Flanged probably would not have had the same problem, since that cartridge is loaded to lower pressure levels than its belted, rimless version.

The above is correct that when both cartridges have high pressure the one with more taper will automatically have more reverse thrust than a more straight sided case of approximately the same pressure! This is while the chamber pressure is at it’s peak.

My statement above is also the reason the straight-sided high pressure case is more likely to be a sticky extraction, and that is because it grips the chamber walls more than the tapered case. The difference in the 458 Win Mag, and the, basically, straight sided 450NE is because though they are both straight-sided cases the 450NE produces far less chamber pressure than 458WM. Both rimless/belted cases cause problems because of different things, but both tied to excessive pressure! The extraction problems for any rimless/ belted rimless no matter the cause are further hampered because of the extraction system necessary for them to work in a double rifle are inherently weak.

Chamber pressure (PSI) effects the more on the chamber walls, and the first four or so inches of the barrels, more than reverse thrust. This is because high chamber pressure causes all cartridges to expand hard against the chamber walls while under peak pressure so doesn’t affect reverse thrust as much as you might think.

The reverse thrust is the phenomenon is one factor in a causing double going off face, but what most effects off face condition is poor lubrication of the mating surfaces of the hook, and pin.

This is the reason all double rifle’s pressure is measured by (CUP), not chamber pressure in( PSI). These are two entirely different things, and affect the rifle in entirely different ways. CUP (Copper Crusher Pressure) measures reverse thrust, of the case against the face of the action, while PSI measures strain on the walls of the barrel, and can cause sticky cases in the chamber! The effect of chamber pressure (PSI) is more detrimental to the chamber walls, while high (CUP) pressures are more detrimental to pushing the barrels away from the face of the action! This difference is why the 375 Flanged Magnum is slightly less CUP pressure than the rimless/belted version! This is the case for all flanged NE cartridges being less CUP pressures than their rimless counterparts.

It all boils down, gentlemen, to the fact that rimless, and belted rimless cartridges were designed for bolt rifles and the flanged NE cartridges were designed for double rifles! In addition to the flanged cartridges, being purposefully designed for double rifles, the fact is that flange allows the extractor shoes to be massive, the make-shift system needed to make the rimless/belted rimless cartridges work in a double rifle are weak in comparison!

With Mr. Murphy always looking over your shoulder, if a failure is to happen, it will predictably happen when it will cause you the most scars! There are two things that simply do not go with double rifles used for dangerous game, # 1 is the word CHEAP and the other is RIMLESS CARTRIDGES !
....................................................

If it were me, I would definitely stick with the .470. Lower pressure makes for longer action life and the rimmed case translates into more reliable and positive extraction.

Plus, as others have said, the .470 is a classic.

The .458 only made its way into doubles because Kynoch stopped loading the big British NE rounds back in the sixties.

No such worries these days.

Just jumped over to the Heym website. It appears that Heym offers what we may refer to as 3 high pressure cartridges for the 88 (300 win mag, 375 H&H, 458 Win Mag).
It would surprise me if a reputable gunmaker would market a dangerous game rifle/cartridge combination that was less than reliable.
The gun initially referred to is listed at $13.5K. Might make an offer for $10K or less. They might sell it in today's economy.
I suspect few folks buy a double rifle and do not practice prior to a DG hunt. If the thing does not work after +300 rounds of practice you should be able to make your decision to sell it or convert it to another caliber. If it does work then it should instill confidence.
If you buy it low, then you can afford a transition to a another 45 caliber if it does not work to your liking.
I might take the leap, if I could buy it cheap
I might add this appears to be a fairly old gun. It has the switch at the base of the forearm that allows you to switch from a ejector to extracting the cases. Not sure how successful this option was and do not know if it is offered any longer. Chris could tell you when and if they discontinued this offering.

I have used my Beretta SS06 o/u chambered in .458 wm with great success on elephant and buffalo. It is an ejector and has never failed me. I know, famous last words. I would not hesitate to use it on future dangerous game hunts. Very accurate and reliable. Wonderful calibre.

Don't know about the 458 caliber. Don't shoot it very much as my only rifle is a Whitworth and it just plain kicks.I do know something about the Heym 88B in a rimless belted. I had one in 375H&H that I have wished many times I still had. It was about the same age as the one in 458 as it had the switch in the same place that the later versions dropped. I probably put around 200 rounds thru it when I had it. It's previous owner was a PH who had purchased it new. How much he had shot it I don't know but it had obviously been carried a lot. I would use it without a moments hesitation on any game anywhere.

By my handle, you will probably think I am BIASED?
458-has too much pressure for Doubles, Period!
458-is not rimmed, consequently too dangerous to use for Dangerous Game with the fragile little extractor that can slip off the rim and leave you out-of-business-at the WRONG time if it failes...AND THEY DO!!
458-never really has come up to real comparison velocity of the 450's or 470, so a weakling in comparison...nee 458 Lott maybe! 1800-1900...not 2150fps needed to compete.
Most 458 doubles don't hold value and best ones have been converted to 450's by competent gunsmiths...like 450 No.2
458- was built as an affordable guide/PH gun...not a good back up by any means...note the maulings that late Rolf Rowher had when his failed...bullets failed too!! Twice I can recall...maybe more?? OTHERS, too??!!
ON, and On...
Yes, they are cheap...and there is a GOOD REASON...buy a good Rimmed Caliber DR...you will be happy you did!!

quote:

Originally posted by 470EDDY:
By my handle, you will probably think I am BIASED?
458-has too much pressure for Doubles, Period!
458-is not rimmed, consequently too dangerous to use for Dangerous Game with the fragile little extractor that can slip off the rim and leave you out-of-business-at the WRONG time if it failes...AND THEY DO!!
458-never really has come up to real comparison velocity of the 450's or 470, so a weakling in comparison...nee 458 Lott maybe! 1800-1900...not 2150fps needed to compete.
Most 458 doubles don't hold value and best ones have been converted to 450's by competent gunsmiths...like 450 No.2
458- was built as an affordable guide/PH gun...not a good back up by any means...note the maulings that late Rolf Rowher had when his failed...bullets failed too!! Twice I can recall...maybe more?? OTHERS, too??!!
ON, and On...
Yes, they are cheap...and there is a GOOD REASON...buy a good Rimmed Caliber DR...you will be happy you did!!

I don't think you are BIASED!

NO, just cold hard facts...I hate to see someone destroy a great British rifle or get hurt Dangerous Game hunting when the darn thing comes apart OR the extractor fails!!
Let me tell you a short story about a 300H&H RIMLESS/Belted in a very nice NEW MODERN Sidelock double built as a 470...the Saudi Prince that ordered it wanted a set of 300H&H bbls...chief engineer said NO...action won't take it...Dangerous! Management and the gun makers went ahead against the engineer's premonition...
Proof went fine with the 470...they fired one proof round in the nice new rifle...300H&H bbls...SPLIT THE ACTION!! New Sidelock-scrap metal!!
NUFF SAID, EH??!!
Might work for a while, but when you need it most...do you want to take the chance??

Good Lord, you guys could be a bit objective.

If one was picking, it is almost a landslide they'd pick the 470 (et al) over a 458 WM.

But we have yet to hear of one failed ejection, one sprung action, one anything as a result of shooting the "high pressure" cartridges. It's all may be, could be, might be, should be, ....

Where are the failures? Maybe the failures got squished under an elephant?

But I don't want one either!

Ask the gunsmiths that have to fix them!! That's where my information is coming from!!

Most owners don't want to admit thier problems...doesn't fit the BMOC frame of the dangerous game hunter AND double rifle shooter!!

I would not choose a double with anything but a rimmed ctg. I have had trouble extracting high pressure belted mags from both a 458 win mag and 375 h and h in Ruger no ones. I would never trust a double with belted ctgs.

If you want a double, hold out for a 450 or 470.

Andy

quote:

Originally posted by eezridr:
It would surprise me if a reputable gunmaker would market a dangerous game rifle/cartridge combination that was less than reliable.

Surprised? Probably. But would you bet your life on it?

Ahh ! Rimmed ! Then you gentlemen have no objection to me taking elephant etc with a 45-70 double !

I do appreciate the technical discussions.

If you add up the variables from what I have been able to witness (TV, books, videos) as I have never been Elephant hunting, it does not look too good for an opportunity to reload; He is just too close. I think you may realize a better chance at a follow up shot with a double than with a bolt, but to reload?? I think this may come into play if the animal is wounded and you want additional follow up shots with it exiting.
To shoot two shots AND reload when an Elephant is within 20 yards and it charging is unrealistic. I am sure there would be some anxiety involved in the ensuing moments further rendering your capacity to implement your well intention auditions in reloading. Same with a bolt, folks may short stroke the bolt. I think it probably best to make your first shot count regardless of what we are shooting. Practice that first shot!

quote:

Originally posted by JabaliHunter:

quote:

Originally posted by eezridr:
It would surprise me if a reputable gunmaker would market a dangerous game rifle/cartridge combination that was less than reliable.

Surprised? Probably. But would you bet your life on it?

The 470, the double rifle round that all others are judged by. It's been there done that and bought the T-Shirt Factory! A large caliber bullet delivered at modest pressure in tropical heat. Manageable recoil.

The 458 Win, Belted high pressure round that drives a .458 caliber bullet fast enough to overcome bullet design and lack of penetration. Kill anything that walks! Able to kill on both ends of the rifle! On the high end, brutal recoil!

Just my opine!

Rusty,

I might like to debate one of your notations. I own a 10.5 lb Heym 88 (470NE). I also own a scoped Browning Safari 458 win mag that weighs between 9.5-10 lbs. I load for both and shoot 500 gr pills at 2150 FPS out of both guns. I actually have been loading RL 15 in the 470 which is a lower recoil load. It has been my experience that the 470 still recoils considerably more than the 458. In fact I believe my 470 recoils as much or more than my 458 Lott shooting 500 gr bullets at 2250 FPS. The Lott probably weighs 10.5 lbs.

quote:

Originally posted by Rusty:
The 470, the double rifle round that all others are judged by. It's been there done that and bought the T-Shirt Factory! A large caliber bullet delivered at modest pressure in tropical heat. Manageable recoil.

The 458 Win, Belted high pressure round that drives a .458 caliber bullet fast enough to overcome bullet design and lack of penetration. Kill anything that walks! Able to kill on both ends of the rifle! On the high end, brutal recoil!

Just my opine!

I will second eezriders notion, I much, much prefer to shoot my 458 lott (ruger rsm) with any load (but especially 450 tsx's at 2250/2300) as opposed to my 470 (heym 88b ph) with 500's @ 2150 or even @ 2000.

Accuracy is better, felt recoil is less (much less!) 20+ rounds in a session are no problem with the lott, even full house 500grn @ 2300. With the 470 5 or 6 rounds and I've got a headache, my finger may or may not be bleeding from the front trigger impact when I fire the left barrel, it depends on whether I'm still really paying attention to form and grip or not.
Let your concentration wander with the 470 and it just plain hurts.
I realize it is mostly about stock design/fit, but that doesn't change the fact that the 470 kicks like hell.

The extra recoil from the 470 is generally considered to be caused by the neck in the case...the restriction caused more rocket effect in the reverse direction than a straight case.
Getting back to the original question about rechambering, the 470 is NOT an option here, unless you rebore too which really gets expensive and not necessary...if you want a 470, sell the 450 and buy one!
That is the reason I mentioned the 450No.2...but I think in looking at the case dimensions in Cart.of the World the 450 31/4 will work too...JJ at Champlins can tell you!

Eez I agree with your use of RL-15. Felt recoil is reduced using RL-15.

I shot my PH's 470 Krieghoff a couple of times right after I shot the Ruger Lott and I couldn't tell the difference.I thought I found the 470 a little more fun to shoot.I shot factory Norma nickel plated ammo for the 470 and hornady factory for the lott.If I am not mistaken they both have similar energies.The Lott's recoil is really felt when pushing 500 grainers to 2300 or especially when pushing 550's to 2130.Would it be accurate to say that the 550 2130 lott load is on the same ground as a 500NE as far as energy goes?

The very simple answer to the question in the context of this thread is that we are discussing both cartridges, one against the other, but most are not considering this is a discussion actually of each in a DOUBLE RIFLE!

Both the 458WIN MAG, and the 470NE cartridges are fine cartridges today but the fact is though they are both good the 470NE is designed for use in a double rifle and the 458 Win Mag was designed to be used in a bolt rifle! That alone should give you the answer to the first poster’s question “WHAT CAN THE 470 DO THAT A 458 CANNOT DO?”

ANSWER IS: Work better in a double rifle!

I know what your saying Mac and I agree with you.I much rather have a large low pressure round in a double when mgazine feeding is not a concern than have a high pressure rimless round in a double.