Bwana-be,

Respectfully, in BIG recoiling guns your shoulder seems to me to be too small to be adaquite for the task.

That's why WELLS and A-Square used the BELTED .460 WTHBY case, headspacing on THAT BELT for their .510 designs!

The way I see it, a .483 diameter bullet, or really pushing it, a .488 diameter bullet, is the MAX for BELTLESS .416 Rigby brass.

They are typically 480 grns, 20 lighter than 500 grn .475 diameter bullets.

So you loose some useful sectional density, bullet weight and shoulder space.

.470 Mbogo has better characteristics by far.

.450 Dakota or Rigby or Tembo have all those zillions of .458 bullets to make use of.

RIP,

When I looked it up, I saw that one nasty definition among the flattering ones and concluded that you did NOT have that nasty one in mind.

RIP,

I JUST NOW SAW YOUR "ORDER" for one of my TO BE BUILT rifles. Care to send $5.000 to get things moving???

Good Night All.

quote:

Originally posted by Bwana-be:

And why make a 460 when you can make a 470?!

I'm wanting a .470 Mbogo, but have noticed that there is nowhere near the bullet selection with the .475 caliber vs. the .458. That could be a major reason to stick with the .458 caliber. Does anyone know who makes some good, strongly made splitzers for the .475 caliber (in addition to the 500 gr. X bullets)?

Well, for .475 bullet selections there are...

- Barnes X & TSX,
- Swift A-Frame,
- Bridger
- Woodleigh

There are probably others I am missing. I really don't think you'll have a problem finding bullets...

Regards,
Dave

There are plenty of bullets available in .475. Granted, there are not nearly as many as in .458, but there are more than enough to get by.

There is the .475 500gr Barnes XLC, the .475 500gr Barnes TSX, and the .475 500gr Barnes Banded Solid.

There are also .475 500gr Swift A-frames.

There are .475 500gr Speer Trophy Bonded Bear Claws.

Northfork makes a .475 500gr soft and solid (I think he is making them, I read here that Mike Brady bought the stock for it).

There are .475 500gr Woodleigh softs and solids.

There are .475 500gr Hawk soft points.

There are .475 500gr Bridger FN solids.

There are .475 500gr GS Custom FN solids.

There are also the .475 A-Square Dead Tough, Lion Load and Solids (available through Midway).

There are .475 325gr and 400gr Hornady XTP's (for the .480 Ruger/475 Linebaugh) that are good for plinking. Barnes, Speer and some others also make pistol bullets in this calibre, see Midway's selection...here

There are lots of cast bullets available for plinking too.

Check out Midway here for their rifle bullet selection, and here for the A-Square and cast bullets.

I am sure there are some I am missing too.

Cheers,
Canuck

The one thing that is good about the selection of .475 bullets is they are all high end bullets. There are some that have a velocity range such as the Woodleigh's. They have an impact velocity rating of 2250 or 2200 fps. I've never had a problem getting .475 bullets and living in the States you have it a lot easier.
Take good care,
Dave

Canuck has covered it well.
But I don't think Mike Brady ever made any of his North Fork Soft Points (a best of best bullet) in .475 caliber, but he has made the Cup Point and Flat Point solid in .475 and .474.

The announcement of the Barnes TSX in .475/500gr for 2006 is great news. At .470 Mbogo velocity of 2500 fps (best) to 2700 fps (abusive of rifle and shooter) it will be the only soft point needed for the .470 Mbogo.

We like the Barnes TSX AND the .470 Mbogo so much here at HA!/DOA that we are adopting that combo as a best of best for the HA!/DOA lineup:

307 Lapua Chui Long Claw
337 Lapua Simba Long Fang
377 Lapua Nyati Big Boss
427 Lapua Kifaru Long Horn
457 Lapua Tembo Long Tusk
470 Mbogo
510 Ndovu
457 Boom Stick

All the above have good bullet availability nowadays, and all will have the Barnes TSX and Banded Flat Nosed Solids in 2006.

Here at HA!/DOA, we just could not improve on the 470 Mbogo, so it is the transitional cartridge between the Lapua Big Five (.308, .338, .375, .423, .458) and the .510 Gibbs/Ndovu.

We just had to have a .475, so the 470 Mbogo is it.

A .475 Gibbs or .475/.408 CheyTac would be a step backward compared to a step forward with the .470 Mbogo.

The cape buffalo and the elephant are both represented twice among the totem animal names for these cartridges, the Super Seven, because they deserve it.

RIP, not sure if you've seen drawings of the 470 Royale, basically a 475-505Gibbs, but it is a monster! Definitely want the heaviest bullets (600g?) to make any sense of it.

Jack, you're probably right about it not beign the best, but if you don't mind the Mbogo at .583", that gives about .058" difference (not sure what the Mbogo's neck thickness is). If you use the same taper, then my little 1.967" body gets .574" and a .038" difference with a .510" bullet and .012" neck thickness. Not the best, but I think functional with a 35* shoulder.

quote:

There are .475 500gr GS Custom FN solids.

I just double checked Gerard's website and I see that his availability of 470 bullets is much better than I thought...

HV's --- 500 and 560 grains
FN's --- 450, 500, 560 and 600 grains

Cheers,
Canuck

ps: RIP, I am sure you are right about the NF's. I probably misinterpreted a post a while back or something. I never checked his website.

Canuck,

Thanks for the bullet update. It'd good to know there are so many excellent options available.

I am thinking about putting a .470 Mbogo together on a cz550 American Safari rifle...

I have a few dummie rounds to play with and it is one heck of an impressive cartridge. I am sure it would do a hell
of a good job on the biggest buff & ele.

I know you have a Tanz. buff hunt coming up with the .470Mbogo and I am certainly looking foward to hearing your report!

Regards,
Dave

Originally by BWANA-BE

Jack, you're probably right about it not being the best, but if you don't mind the MBOGO AT .583", that gives about .058" difference (not sure what the Mbogo's neck thickness is). If you use the same taper, then my little 1.967" body gets .574" and a .038" difference with a .510" bullet and .012" neck thickness. Not the best, but I think functional with a 35* shoulder.[/QUOTE]
________________________________________________

TO BWANA-BE,

A MBOGO AT .583"??? I checked what I had written at the top of this page, that's not what I am seeing, please take another look!

I did mention BULLETS with .483" or .488" diameter in a 416 RIGBY case which has a base of .588" at least.

For me, bullet diameter .483 or pushing it .488 MAX in the .416 Rigby brass, which has a .588 - .590 cartridge base diameter.

I am all about HUNTING, so my ammo must have field friendly characteristics.

That's why I'd want a guy at the absolute MINIMUM, to have .100" difference in the diameters of the cartridge base and the bullet, and really, I'd never go less than a .366" bullet from a 30-06 case which is .470" at it's base. A difference of .104".

RIGBY BASE MINIMUM .588
BULLET DIAMETER .488
DIFFERENCE .100 - my absolute "line in the sand" (FOR SOME ONE ELSE)

If a guy insisted on this, I'd live...

But I'd much rather see him pick the .483" bullet so the spread would be .105" - my preferred "line in the sand". I TAKE THE .104 ABOVE JUST BECAUSE YOU GOTTA BREAK A RULE NOW AND THEN.

And with so many more bullets available in .475 and 2X again as many available in .458 WHY WOULD A GUY WANT THE RARER .483 OR .488, JUST TO BE A LITTLE UNCOMMON, OK, THAT'S COOL WITH ME, I HATE "OFF THE RACK..." I LIKE STUFF A LITTLE UNIQUE, BUT NOT UNRELIABLE!

Jack...hope you don't mind...I edited your post slightly so it would be the same width as the rest (it was the line that made it extra wide).

Cheers,
Canuck

quote:

Originally posted by Canuck:
Jack...hope you don't mind...I edited your post slightly so it would be the same width as the rest (it was the line that made it extra wide).

Cheers,
Canuck

Your "da man!!!" I hate it when posts go WIDE!!!

Jack, that was a typo. C'mon. I was refering to the bullet size, as you were.
The thrust of my post was that with a given taper and body-to-neck difference, the neck gets bigger as the case gets smaller. If you're simply looking at base-to-bullet without considering body length, then give it a really long body and you don't get your shoulder you want.
Even so, I see that my 'cat doesn't meet your minimum, just wanted to point out that it wasn't as far off as you might first think if only considering 3.75" rounds.
BTW, forgot to mention, I contend the reason A-Square used the Wby case is that at that time there was no other real choice. Now that there is a choice, it would still be silly to make a commercial 510 Rigby, it's just not why they did it.

I should mention, I had no intention of taking this round up against an elephant when I designed it, so I can only take with a grain of salt admonishments about its reliability. More than anything just a drafting excercise that lead to a mini-obsession. For the record, I'm much more likely to actually chamber it in .475" for a number of reasons; just insist on insting that it would work. And by work I mean headspace and send a 570g out at 2150 at around 50kpsi. To me the whole idea is enchanting. But a 500g .475" going 100fps faster just seems even more so. (Plus, it would make a great lil' bro Mbogo!
;-)

Cheers!

RIP & BWANA-BE - please, both of you comment on the following, SPECIFICALLY #'S 9 and down:

1-As I have said many times, I do NOT pretend to have ever done ANY of this myself, I TALK ALOT TO OTHERES WHO HAVE, AND READ ALOT.

2-I hope to one day REALLY do all this.

3-I did not perceive your TYPO, SORRY I thought you meant what you wrote and I did get confused.

4-I HAVE NOT BEEN ADDRESSING THE CASE TAPER OR NECK ANGLE OR ANY OF THOSE DETAILS, I AM NOT FEELING KNOWLEDGEABLE ENOUGH!

5- AM STRICKLY LOOKING AT HAVING A .105 SPREAD BETWEEN THE TWO DIAMETERS, BULLET AND CART. BASE.

6-THIS ALLOWS FOR A GOOD SIZED RELIABLE SHOULDER TO BE FORMED.

7-IN THE FIELD THIS IS A MUST, OR YOUR ROUND NEEDS AN ACCURSED BELT.

8-(.300 H&H Mag and others)

9-PICTURE A "CARTRIDGES OF THE WORLD" TYPE CARTRIDGE DRAWING FOR A BELTLESS, RIMLESS DESIGN

10-IF YOU PUT A PIECE OF BRASS UPRIGHT ON A TABLE, ON EACH SIDE OF SAID BRASS - FROM THE BASE UP TO WHERE THE SHOULDER STARTS (TO TURN IN) THOSE SIDES, THOUGH TAPERING IN SOME, SHOULD BE "RELATIVELY NEAR" PERPENDICULAR TO THE BASE, (.416 RIGBYISH).

11-NOW MAKE A "DAKOTA ARMS" TYPE OF SHOULDER FOR EXAMPLE, http://www.dakotaarms.com - click on ammunition section to see drawings.

12-NOW FINISH THAT ANGLED PART OF THE SHOULDER AND START TO GO STRAIGHT UP AGAIN ON BOTH SIDES.

13-THIS TIME THESE VERTICLES, (THE NECK SIDES) AUGHT TO BE REALLY ALMOST TRULY PERPENDICULAR TO THE CARTRIDGE BASE TO GIVE A GOOD HOLD ON THE BULLET.

14-(THAT'S WHY ON A .495 A-SQUARE, A. ALPHIN MADE THE "GHOST NECK", (.460 WBY BRASS, tapered sides from belt up about 88% of the distance to the neck opening, then made a NECK right there with near parallel sides to it), JUST TO BETTER HOLD THE BULLET AND MADE RELOADING EASIER.)

15-IF YOU FOLLOW THIS TRAIN OF THOUGHT, (starting at # 9) TO CREATE HUNTING ORIENTED CARTRIDGES, YOU SEEM TO COME OUT A WINNER.

16-YOU GET GOOD EXTRACTION, RELIABLE HEADSPACING, AND SO ON AND SO ON...

17-BUT YOU NEED THAT .105" DIFFERENCE BETWEEN THE BASE DIAMETER AND THE BULLET DIAMETER TO GET A LARGE ENOUGH SHOULDER

17-I hope I have been able to put what's in my head into this entry.

Looks good to me ajck. Only thing I would add is that they "look" perpendicular but aren't. They are tapered, and start big at the bottom and go a bit smaller as you head to the top of the body, before shoulder (on the order of .008-025"/inch.) Now, if the issue is (and I think it is) how much difference there is between the body thickness and the neck thickness, then you can see how the closer to the base you are, the greater the difference there will be for a given caliber on a given case.
(FYI, As I understand it, a god rule of thumb is .002-4" difference between the top of the neck to the bottom of the neck to allow for extraction; otherwise, the neck can expand into a straight tube with no release.)

Bwana-be, I LOVE you "catch phrase."

quote:

When catapults are outlawed, only outlaws will have catapults

You tell 'em pal!!!

quote:

Originally posted by BigFiveJack:
5- AM STRICKLY LOOKING AT HAVING A .105 SPREAD BETWEEN THE TWO DIAMETERS, BULLET AND CART. BASE.

7-IN THE FIELD THIS IS A MUST, OR YOUR ROUND NEEDS AN ACCURSED BELT.

8-(.300 H&H Mag and others)

9-PICTURE A "CARTRIDGES OF THE WORLD" TYPE CARTRIDGE DRAWING FOR A BELTLESS, RIMLESS DESIGN

...17-BUT YOU NEED THAT .105" DIFFERENCE BETWEEN THE BASE DIAMETER AND THE BULLET DIAMETER TO GET A LARGE ENOUGH SHOULDER

.

B5J,
actually.. you don't.. these are desirable states, but not requirements. I can understand on your point 5 that YOU are strictly looking for that... but not everyone else is. The 470 capstick, the 458 lott/win, 375 whelen, the various versions of the 400 whelen, almost all autoloader pistol rounds, the 30carbine, the 6mmipsc, (the various .510s all BARELY make this number) and many many many more don't meat you .105 diameter delta.

There are fewer issues with a belted bolt gun round than a rimmed one. It's only accursed in opinion... The 300 HH is a mile easier to get to feed than a 404 jeffery, assuming you are starting from the same basic gun.

You've got soem good opinions, just remember, that preferences aren't always facts.

quote:

Originally posted by Bwana-be:
Looks good to me ajck. Only thing I would add is that they "look" perpendicular but aren't. They are tapered, and start big at the bottom and go a bit smaller as you head to the top of the body, before shoulder (on the order of .008-025"/inch.) Now, if the issue is (and I think it is) how much difference there is between the body thickness and the neck thickness, then you can see how the closer to the base you are, the greater the difference there will be for a given caliber on a given case.
(FYI, As I understand it, a god rule of thumb is .002-4" difference between the top of the neck to the bottom of the neck to allow for extraction; otherwise, the neck can expand into a straight tube with no release.)

BB,
I don't know where you read this, and I am certain it applies in some smaller cases, however, big bores/dangerous game rounds are generally given a fairly generous "clearence" on the reamer... and a sloped neck is a no-no. However, a properly cut reamer will have a slight drift in the neck (and body) over case design... in dgr's that generally .003 or so in diameter, that will let the brass FALL out of the chamber...

Give manson a call if you don't agree

jeffe

Bwana-be and I were going back an forth a little, but it was not at all in nasty tones, at least I did not feel it was.
If anyone did, I am sorry.
He and I both admitted we are NO experts, just amatures.
I do not insist the world use my guidelines, but if you are not headspacing on a rim (like 500 NE) or on a belt (.375 H&H) than in a hunting rifle you must headspace on a good shoulder (30-06, 505 Gibbs).
That's what I meant in #7 above.
It's all my opinion, and not based on any experience.
I am not writting of any rebated rim carts. like 404 or 500 Jeffery.
R/R's have more issues and I don't even want to try those out.
Dakota Arms Proprietary Ammo is Rimless, not rebated nor belted. 30-06ish but bigger just about 404 Jeffery sized.
Good basis for much wildcatting I think.

Jack,
on rebated rims --
there's a point where its an issue (500 jeffe and 425 WR for example)..

and a point where it's not..

the first 50 years of the 404 jeffery ...

some folks feel ANY is bad. and I humblely point at the 404...(rebated outside of design, i might add)

and some folks hate belts...

and I humblely point at the 375 HH


Rebated rims potentially have feeding issues.. yep.. agreed... and so does an 8x57... just takes a better feeding expert gunsmith

would I build another 500 jeffe? not on a bet
would i build a 510 wells? (nearly the same rebate) ... probably

jeffe

Jeff, sorry I wasn't clear. I was talking in terms of chamber, headspace. Yes the unfired, fully-formed case should have a straight neck. ;-)

Yes, of course when you size down a neck and then seat the parallel sided bullet into the neck, of a bottle-necked case, the loaded cartridge neck is going to be parallel sided, as Bwana-be says.

Some precision chambers and chamber reamers will be only .001" different from neck-1 (larger at shoulder juncture) to neck-2 (smaller at case mouth). This is still a few thou bigger than the brass neck all around, in most rifles.

There has got to be few thou slop around the neck for a DGR, as jeffe says, so the neck can elastically expand to release the bullet and then spring back to sub-chamber neck size so as to fall out of the chamber effortlessly.

Everybody is right here. Especially BigFiveJack, with his "empirical rule" of desirable case head to bullet diameter difference: 0.105". I like it.

This accounts for the entire cartridge body taper plus shoulder step/taper, plus neck thickness down to bare bullet.

Think of a nicely medium-body-tapered cartridge like the .416 Rigby and the identical taper of the offspring .338 Lapua Magnum. The Rigby has an abrupt 45 degree shoulder, and the Lapua has a slick-medium 20 degree shoulder.

Body taper itself may work as a "secondary shoulder."

Think of the .404 Jeffery with minimal body taper and very gentle 8.5 degree shoulder.

Many ways to skin a cat, but all the unquestionably faultless ones fit BigFiveJack's "Law."

That's the wildcat's meow and the domesticated "cat"-ridge's purr.

To RIP,

Thank you for your "pat on the back".
As an observer in this study I seem to have come to a good working conclusion.
I love this site as I get so much info here.
Thank you to ALL of the guys who are sharing their real working knowledge with people like me here!

Rip and others,

This is probably food for another post but...Does the 460G&A headspace well enough for a DGR?
Remington brass of course.

I love the concept but am a little hesitant to have one built.

Jamie

Jamie,
please do a search on 458 AR... which is a shorter than GNA and based off rum brass...

jeffe

x-man,

If you want a .458 caliber bolt action rifle in a design choice that seems really right to a lot of people concider 450 DAKOTA or 450 RIGBY or 450 TEMBO.

Please check your Priv. Messg.

quote:

Originally posted by BigFiveJack:
x-man,

If you want a .458 caliber bolt action rifle in a design choice that seems really right to a lot of people concider 450 DAKOTA or 450 RIGBY or 450 TEMBO.

Please check your Priv. Messg.

or 458 AR ...

that fits in a standard length action

Yes, but .550" to .458" is only .103"! ;-P

No offense guys but you can headspace perfectly on a .010/side shoulder. I made just such a widcat years ago and everyone said it would never work, that the firing pin strike would move the brass foreward and destroy the headspace. Pure CRAP! Just try and move a case with just such a shoulder. Maybe you can move the headspace with a 10lb sledge hammer. maybe not! I would not be surprised if a .005 shoulder worked just fine. There are alot of internet myths and Experts out there. Beware of the BS and do the experiment.-Rob

quote:

Originally posted by Robgunbuilder:
No offense guys but you can headspace perfectly on a .010/side shoulder. I made just such a widcat years ago and everyone said it would never work, that the firing pin strike would move the brass foreward and destroy the headspace. Pure CRAP! Just try and move a case with just such a shoulder. Maybe you can move the headspace with a 10lb sledge hammer. maybe not! I would not be surprised if a .005 shoulder worked just fine. There are alot of internet myths and Experts out there. Beware of the BS and do the experiment.-Rob

Rob,
I am here to tell you that .038 total on a sharp angle will stop a freight train... or .032, just like the HH case. ,, i love "do the experiment"...

of course, knowning that, .105 should meet the requriments of headspacing at least as well... but would I limit myself to that? no more than I would limit myself to 80# of recoil

jeffe

Robgunbuilder,

Not being critical, just asking because my interest is very narrow, Dangerous Game worthy calibers.

Please give DETAILS of your w/cat.
Was it a BIG bore, heavy recoiling design?
Would a guy going up against a charging Dang. Game beast want to risk his life and his client's life on your design?

Jack,
take a .500 brass rod and drill a 15/32 hole in a steel plate.. and let us know how many time you have to hit it with a 10# hammer to get it to go in .010". Heavy recoil doesn't have anything to do with altering headspace.

Your paradigm, laid out in a simple fashion, as I understand this, for your choices in desirable bolt actions rounds are
1:unrebated
2:.105" difference from bullet to base
3: unbelted

and yep, your paradigm works, EVERY time, for those rounds. heh, even the 376 steyr ffits perfectly. Anything that fits your paradigm will work VERY well. and anything with a rim in a double gun will, as well. Not slighting any round that fits... it's rather self limiting though, especially when the rounds get large and you have engineering concerns on stagger feeding vs single stack

However, this excludes MANY excellent rounds, starting with all the HH based cases, and then the weatherby wildcats. 375 whelen, which no one has ever questioned headspace on, which is .098" under your formula. 400whelen/411hawk... tough one, but it does work. 458 win and 458 lott, 470 capstick, 500a2, 510wells, and the mightly 404 jeffery - which spent it's first 50 years was rebated by "accident".

On headspacing, directly, I trust that Dave Manson should be considered an expert in the area. The 470 ar, which I nearly canned due to perceived headspace, was discussed with him, especially when I was about to back out. His thoughts were it would work perfectly well, and feed very well. It does.

When one accepts that some rounds could be measured differently for suitability, one accepts that those parameters are biases, rather than engineering constraints.

jeffe
remember, the 45 acp headspaces of fthe case mouth... don't hear of it haveing design failures, does one?

Jeffe, that's not a fair comparison and oyu know it! :P
I've always figured part of the idea came about in the context of mass-produced guns, with standard tolerances, which just isn't the same when you're building one wildcat (or even twenty.)
If it weren't for the near-impossibility of me getting it to work, I would invest in the 45* shoulder ala Rigby, but there's no way with my equipment I can manage that. I don't actually even know how they do it at the factory.
The H&H case has .021" difference, right? (.532-.511) Anyway, not much at all. But it's not something that could be moved during sloppy reloading - again an issue with mass-production.

Anyway, in spirit of the original thread here, I want to say I think the Mbogo is the coolest 'cat around. Even cooler now that my gunshop has a CZ Rigby. I can hear it calling from the highway!

quote:

Originally posted by Bwana-be:
Jeffe, that's not a fair comparison and oyu know it! :P

sure it is!! I am allowing a hammer, rather than just hands

quote:

Originally posted by Bwana-be:
I've always figured part of the idea came about in the context of mass-produced guns, with standard tolerances, which just isn't the same when you're building one wildcat (or even twenty.)
If it weren't for the near-impossibility of me getting it to work, I would invest in the 45* shoulder ala Rigby, but there's no way with my equipment I can manage that. I don't actually even know how they do it at the factory.
The H&H case has .021" difference, right? (.532-.511) Anyway, not much at all. But it's not something that could be moved during sloppy reloading - again an issue with mass-production.

Anyway, in spirit of the original thread here, I want to say I think the Mbogo is the coolest 'cat around. Even cooler now that my gunshop has a CZ Rigby. I can hear it calling from the highway!

yep!! the 470 mbogo is, without a doubt, the supreme coolest wildcat on the planet!

jeffe

quote:

Originally posted by jeffeosso:

yep!! the 470 mbogo is, without a doubt, the supreme coolest wildcat on the planet!

jeffe

You're preaching to the choir!!!

Right on guys...the .470Mbogo is damn cool!

I have never really wanted a wildcat........until now.

IMHO Dave's cartridge fits a big bore 'bolt rifle' niche and I hope it gains in popularity. He certainly has done a hell of alot of testing/work in bringing this cartridge to life and I have benefited quite a bit from reading his website and learning from his experience.

Regards,
Dave

quote:

and I hope it gains in popularity.

Me too. The fact that it is not yet in "Cartridges of the World" is a travesty!

I also agree that it is the coolest 'cat going. Just wonder though, does it then logically follow that the people that have one are also the coolest?

Cheers,
Canuck

quote:

does it then logically follow that the people that have one are also the coolest?

You know after thinking on it....I'd have to say yes!

Best,
Dave