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boom stick,
Since you are TA!/VPM (Technical Advisor and Vice President for Marketing) for HA!/DOA, you should run with your idea.

When you asked about a 3.4" COL .458 Tembo, I went to my ammo box and pulled out this dummy. It is a .458/350 grain Barnes X-Cannelured bullet seated in a fireformed .458 Tembo case, and crimped.

It measures 3.380" COL.

A heavy flat nosed solid could be adapted to this length as well as some other bullets.

The neck of the .458 Tembo is perfect as is, caliber long. Necking up the .338 Lapua (2.724") to .458 caliber makes the brass length shorten to 2.666", the mark of the beast.

To make other bullets fit or to reduce the COL to 3.340", the neck could be trimmed a smidgeon without hurting the cartridge at all.

This will make the .458 Tembo perfect for the standard length Mauser 98, Stainless Ruger M77 MkII, and any old Winchester Model 70 from unwanted 7mm RemMag on up. A lonely .458 WinMag could have its chamber cleaned up by a .458 Tembo, but that would leave the .458 WinMag throat as is, not a bad thing. That would still allow long-nosed ammo to be chambered in the short-boxed rifle.

This cartridge has everything. It has no faults. It will top the .458 Lott in a shorter action.

Actually it would be perfect in a 3.600" boxed .375 H&H Winchester M70 Classic Stainless.
They have done that one up as a .416 Rigby, but that opens the length of the action unsafely.

Get the magazine box width right in a 3.600" standard M70 and you can go to town with no worries.

I want one too: 2400 fps with 500 grainers in a 22" barreled Winchester Model 70 Classic Stainless, or back off to .458 Lott performance at really low pressures. thumb

I still prefer the Long Nose seating and throating for a 3.8" COL in a true Magnum action.

.458 Tembo-Faultless
 
Posts: 28032 | Location: KY | Registered: 09 December 2001Reply With Quote
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rip...

congrats!

you have a new baby!!! cheers

is this the 458 jumbo? little brother to tembo?

i think the neck trim is the best idea to make it easier...the best thing is you just need to neck up a lapua and maybe a light trim on length!

is this your next project rifle?

who wants one? (besides rip and me)

the a.r. rounds have their appeal as well so they are cousins being the same length. we could have both wildcats without turning into the hatfields and mccoys i hope.

shes a beeaaauuuute! (crocodile hunter voice)

cant wait to own one...

as well as 2 a.r. rounds Big Grin


577 BME 3"500 KILL ALL 358 GREMLIN 404-375

*we band of 45-70ers* (Founder)
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BS,
This is no competitition.
We are simply offering the best design ideas for anyone wanting Faultless Rifles and Ammo.
It can be done by anyone who gets his duff off the couch.

.338 Lapua Magnum brass is only about $1.50 per piece. Ditto Jamison .505 Gibbs brass.

There is no better, and there is definitely no false economy here.

We offer no wood upgrades and even recommend skipping the wood altogether and going directly to a McMillan stock. thumb
 
Posts: 28032 | Location: KY | Registered: 09 December 2001Reply With Quote
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the pic reminds me of a 500 jeffery (without the rebate of course) Wink

so correct me if i am wrong but all you need to do is neck up in three stages stuff and crimp.

get your 7rem and open up the boltface. put in a lapua reamer make it feed and slap on a 458 barrel

or get your 338 lapua slap on a 458 barrel and ream.

???


577 BME 3"500 KILL ALL 358 GREMLIN 404-375

*we band of 45-70ers* (Founder)
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Posts: 27615 | Location: Where tech companies are trying to control you and brainwash you. | Registered: 29 April 2005Reply With Quote
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quote:
Originally posted by boom stick:
the pic reminds me of a 500 jeffery (without the rebate of course) Wink


If you trimmed the neck down to sub caliber length then it would look like a mini-me 500 Jeffery with no rebate. The 500 Jeffery has only 0.344" of neck length.

Call it the ".458 Dumbo" animal: fits any standard Mauser M98 with any bullet if you make the neck short enough.

Cool? Actually, trimmed to 2.500" brass length, the .458 Dumbo would have only 0.292" of neck length.
.458/.292 = 1.57 caliber/neck ratio .458 Dumbo
.510/.344 = 1.48 caliber/neck ratio .510 Jeffery
Not
too
different:
1/1.57 = 0.64 neck/caliber ratio (.458 Dumbo)
1/1.48 = 0.68 neck to caliber ratio(.500 Jeffery)

Could be fun in a Ruger All Weather M77 MkII stainless. Cool tool. thumb

As far as building the rifles, being TA!/VPM for HA!/DOA you ought to have this down by now. Lead on!thumb

Another star is born! The .458 Tembo trimmed to 2.500" becomes the .458 Dumbo. clap
 
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Holy Cow!
The .500 Jeffery and the .458 Dumbo both have the same shoulder angle: 20 degrees!

And No Rebate on the .458 Dumbo. thumb

If the .338 Lapua is fire formed in a .458 Tembo chamber, the 2.724" brass ends up at 2.694" length.

If the .338 Lapua is necked up in 2 steps
first: .338 to .375
second: .375 to .458
using RCBS tapered expanders: never a neck split yet.

I think we should standardize the HA!/DOA big five at brass overall length of 2.700" with trim to length of 2.690".

However with the .338 Lapua-Simba and .300 Lapua-Chui being CIP standardized at 2.724" brass length, trim to 2.714", we might want to go with that, when we get the properly headstamped stuff going for all calibers.

69 mm nominally whichever way it goes.

.458 Dumbo will be a 64 mm case length, nominally, for the Euro-lingo.

.510 Bibi is 76 mm.
 
Posts: 28032 | Location: KY | Registered: 09 December 2001Reply With Quote
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o.k to get the names down...

far seated bullet to h+h mag length in 2.66" case, 458 tembo
bullet seated to 3.4 c.o.a.l., 458 jumbo
case trimmed to 2.5 for standard action length, 458 dumbo

is this correct?

glad to see the dumbo with such a pedigree cousin Big Grin that is like having prince charles at the thanksgiving table


577 BME 3"500 KILL ALL 358 GREMLIN 404-375

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turn this 7mag into a dumbo or jumbo

(Ruger All Weather M77 MkII stainless)


577 BME 3"500 KILL ALL 358 GREMLIN 404-375

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.458 Tembo/Jumbo/Dumbo, as you say. Good work!thumb
 
Posts: 28032 | Location: KY | Registered: 09 December 2001Reply With Quote
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question is for the lever people will it work in a b.l.r.?


577 BME 3"500 KILL ALL 358 GREMLIN 404-375

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can you work your magic and post all three together in a pic please next to a 500 jeffery!


577 BME 3"500 KILL ALL 358 GREMLIN 404-375

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quote:
Originally posted by boom stick:
can you work your magic and post all three together in a pic please next to a 500 jeffery!


No can do, no have .500 Jeffery. I am smarter than that!

Correction:
.458 Tembo is long nose COL 3.800"
.458 Jumbo is short nose COL 3.600"
.458 Dumbo is short necked to COL 3.340"

Later I shall post a .458 Tembo/Jumbo/Dumbo. wave
 
Posts: 28032 | Location: KY | Registered: 09 December 2001Reply With Quote
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there are about 200 500-jeffery owners here i am suresomeone can send you one...ask jeffeosso to send you one he has one right? bewildered


577 BME 3"500 KILL ALL 358 GREMLIN 404-375

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what will be the % of performance or case capacity diff. between them with the identical 500 gr bullet?


577 BME 3"500 KILL ALL 358 GREMLIN 404-375

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p.s.

cut that 510 bibi (510-505 gibbs) down to fit in a 375 h+h model 70 stainless action. that will raise some eyebrows... Eeker


577 BME 3"500 KILL ALL 358 GREMLIN 404-375

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No point in it boom stick. I just don't like the hassle of begging.

Don't get too reckless with your technical advising, eh?

I will send you a set of Tembo/Jumbo/Dumbo dummies for your assistance.

Maybe you could find a .500 Jeffery to do the photo with if it turns your crank.

Now back to the .510 Gibbs-Bibi: maybe she deserves a better name than "Grandma."

The other Swahili word for elephant: Ndovu

So be it, enough fun at Grandma's expense.

The ".510 Ndovu" is born, a .505 Gibbs necked up to .510 and shortened to 3.010 max brass length.

With the GSC FN .510/570 grainer at XXXX fps, a frontal heart shot on elephant(or brain shot from a tree stand) animal might be able to clip the tail off as it exits the rear end, saving one chore of trophy care.

The .510 Ndovu will dwarf the .500 Jeffery.
The .510 Ndovu will have no rebated rim.
The .510 Ndovu will have a full caliber length neck.

The .500 Jeffery will be pitiful by comparison.
It belongs in a full length Magnum Mauser anyway, so why not correct all its deficiencies?

If you do that, what do you get?:

.510 Ndovu.
 
Posts: 28032 | Location: KY | Registered: 09 December 2001Reply With Quote
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please throw one in the mail if you can spare one Big Grin


577 BME 3"500 KILL ALL 358 GREMLIN 404-375

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Where does this end? rotflmo moon
 
Posts: 28032 | Location: KY | Registered: 09 December 2001Reply With Quote
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bewildered

i dont know but you have a great line up of cartridges.

what is the unmodified neck length of a 505 compared to the ndovu?


577 BME 3"500 KILL ALL 358 GREMLIN 404-375

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rip...you could also do jeffeossos idea and make the 550 ndovu

to quote jeffeosso...

Rip,
theres no real descernable difference is recoil from a 510 600 at 2500 vs a 550 700 at 2300...

wasn't sure this as about "mere mortals" anyway

and actually the 505 gibbs case, with just a .550 expander in it, has FAR more than neck than a 470 mbogo...

finish the job, sirrah.. finish the job

jeffe


577 BME 3"500 KILL ALL 358 GREMLIN 404-375

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another would be to move the shoulder back and follow jeffeossos idea then trim case to 2.85 and neck to 550 or 510 but that is a lot of work.


577 BME 3"500 KILL ALL 358 GREMLIN 404-375

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.550 Gibbs, Bad idea:
.640 " - .550" = 0.090"

.470 Mbogo, Good idea:
.590" - .475" = 0.115"

boomstick:
You have just been demoted to "Comedian" at HA!/DOA. I have given you many chances to learn some technical advising here, but I am afraid it is hopeless. homer
 
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the idea was to lose some body taper not mess with tiny shoulder...

if there are some things i do not understand yet please inform me.

the 510 ndovu and the 458 tembo jumbo and dumbo are a handfull enough. hope to see pics soon. thumb


577 BME 3"500 KILL ALL 358 GREMLIN 404-375

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quote:
Originally posted by boom stick:
rip...you could also do jeffeossos idea and make the 550 ndovu

to quote jeffeosso...

Rip,
theres no real descernable difference is recoil from a 510 600 at 2500 vs a 550 700 at 2300...

wasn't sure this as about "mere mortals" anyway

and actually the 505 gibbs case, with just a .550 expander in it, has FAR more than neck than a 470 mbogo...

finish the job, sirrah.. finish the job

jeffe


Quoting jeffeoso's nonsense about the .550/.510 Gibbs was the last straw.

Go back and read my correction of him at the time he posted that.

You are on your own on this one.
Now I am afraid we are going to have to let you go from your low paying (no paying) job (volunteer work) at HA!/DOA. Even comedians and candy stripers have to be smarter than this.
 
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the question wan not meant to offend...

again the new rouds will be great congrats cheers


577 BME 3"500 KILL ALL 358 GREMLIN 404-375

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read the follow up post on the next page...you are right, the 510 is the biggest you can go and it is not worth all the work and loss of taper...that is why you are the boss and i am the unpaid lacky...good luck Wink


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boom stick,
Don't take this stuff too seriously.
I'll send you some dummies to play with. thumb
 
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that would be great thumb

what is your guess of the % diff in performance from the tembo to the dumbo?


577 BME 3"500 KILL ALL 358 GREMLIN 404-375

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the best idea is the 458 and 338 switch barrel Smiler

22" for the 458, 26" for the 338


577 BME 3"500 KILL ALL 358 GREMLIN 404-375

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WOW! Boomer's eating up these Lapua and RUM cats up more than me!! You know, theres nothing better than sitting around the fireplace in your smoking jacket, sipping on brandy, playing with your wildcat dummy rounds!! beer
Some 470 Lapua (dont remember the exact name, sorry)and RUM cat dummies would be nice. I could put em under my pillow and maybe the custom rifle fairy would replace the dummy with a custom rifle on a GMA action!!

Sorry for the smartass comments. These things happen when you are window shopping without any cash... killpc
 
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thats o.k.

when i shoot these big boomers it will all be worth the smile on my face...

i dont need a fancy gun just a reliable stainless one.

half the enjoyment in life is dreams and the potential even if they dont quite make it to fruition. in a few years i will have all the rifles i want ( animal within reason) and i will be enjoying them emensely Big Grin

as the proverb goes...the best revenge is living well cheers


577 BME 3"500 KILL ALL 358 GREMLIN 404-375

*we band of 45-70ers* (Founder)
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Posts: 27615 | Location: Where tech companies are trying to control you and brainwash you. | Registered: 29 April 2005Reply With Quote
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Hey, that little guy is close to what I have in mind. Trim the case to 2 1/3 instead of 2 2/3" and neck to .475" bullet, put in M70 SA and voila!
Should have the capacity of the Lott more or less, though I'm thinking my rifle will be a bit light for full Lott loads.
That round do look great though. Just a bit too long, and not quite fat enough bullet....
;-)


Cum catapultae proscriptae erunt tum soli proscript catapultas habebunt.
 
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