The big Lazzeroni cases are .557 at the shoulder, tapering down from .577 at the base. They will work for the 470 Ar. So, they are more expensive at 2 bucks a pop, but they are STRONG and will last a LONG time at a puny 60,000 psi.

Am I dreaming, or is this a positive UPDATE...?

Will I take my 1st Big Game rifle ( 700 / 7mm Rem.Mag. ) and turn it into a .475?! (...er, uh, exCUSE ME --- .470! )

Will my .375 ULTRA be jealous?

Will my BAR MkII Safari/BOSS in 7mm Rem.Mag. revel in its sole role as the 'Big 7'...?

Only time will tell. Tune in next week for these and other hard to answer questions...

There are two reasons for choosing the ultramag brass, and the cost of the brass isn't the primary one. The primary design goal is the ability to grab an off the used rack 7 rem mag as a donor action, and with nothing more than a re-barrel, make it an AR monster masher.

The u/m brass is more than strong enough for 500 gr @ 2200 fps and will last a long time, and at $50/100 cases vs $200/200 is a big deal. more imporantly it's the cost of having the bolt and extractor as well as feed rails and magazine opened up where the savings are, or starting with a large action.

Let's face it, you can get a used a 7 rem mag for $250-300, and for another say $400 get a 470 AR barrel screwed on, add dies and brass and a couple bucks to open up the barrel channel if you don't do it yourself and you're good to go for a nominal $1000. The other option is start with a 416 Rigby CZ for some $700-800 and have a 470 M-bogo barrel put on for the same $400, add brass and dies and you're out at least $1500.

Jeffe

Ed has the technique correct as to necking to a crush fit, in the chamber, off of a cylindrical case.

I have worked extensively with the 411 Hawk and all the pressure data on that cartridge came from my testing. Done as Ed has said, there are no problems at all with proper headspace. As a check to how strong that small shoulder is, just do the necking a little short. You will break your hand trying to pound the bolt shut getting the round to chamber the first time. Been there, done that.

My only question/suggestion is for the necessity of the 40 degree shoulder angle. It is alluring and one would presume that the higher angle on a small shoulder will increase your odds of good headspace. I can tell you that it will take several firings (4 or more heavy loads) to get that tiny shoulder to actually take a 40 degree angle. I don't recall the 411's angle but I can tell you that it also takes several heavy loads. Even seeing that the case did not take the high angle after one or two firings, the case still headspaces perfectly the next time. What I am getting at is that if the case still works well at a lower angle than the chamber, maybe it would not need such a high angle to begin with. I don't think that the steep angle will get you anything except that warm fuzzy feeling that you are doing good (not to be underestimated )

Mike

those are good numbers paul

Paul,
I think you meant $200/100...

thanks for the hawk info mike since this is meant to be a DGR round, i'll take whatever warm and fuzzy i can get
... boomstick will be happy.... that hawk works in a lever gun!!

jeffe

Hi Paul,
I still think your going to have to do some work on your feed ramp and follower with the 470 AR. Changing it from a 7mm mag and having the cartridge lead into the chamber with a .475 bullet instead of a .284 will create a pile more lift as is hits the top of the feed ramp and probably push the bullet into the top of the chamber entrance. You will have to wait and see if the rails need to be changed to let it exit the magazine box properly. But with the fatter cartridge don't be surprised if they require work.You should make sure that the entrance to the chamber is chamfered after it's chambered to help avoid some of the feeding issues you come across.. The shoulder on the 7mm mag is .490 and the mew cartridge will be fatter and have less taper so you might want to look at reshaping the follower so the new cartridge will lay down on it properly which will help with magazine capacity. It will be interesting to see what the magazine capacity ends up being. Just more ideas to think on. I hope this project flies well for you guys. It's a big commitment.

PS that $1500.00 or $500.00"s more will put you in a whole different world.
Take good care,
Dave

I watched all the .470 Mbogo videos.
"Monster Masher" is a good term, and "Shits & Giggles" is as good a reason as any as I can think of to put together a rifle/cartridge such as is being discussed.
Watching everybody LAUGH after they shot the Mbogo was a blast. Who WOULDN'T?! Man, that's some POWER!
I think "YOWZA!!!" is what I'd say after the first shot.

"TROLL KILLA"

quote:

boomstick will be happy.... that hawk works in a lever gun!!

jeffeosso...wont all the a.r. rounds work in a b.l.r.?

the a.r. carts and the blr will have people re-thinking the idea of a dgr rifle

I've been following this threat with great interest. The 470 AR could be just the ticket to get me a big boomer that won't cost an arm and a leg. I have a 7mm rem mag on a Tikka M695 magnum that I don't shoot much anymore (don't need it. it's been replaced with a 300 wby on the high side and a 260 rem for the wife on the low side). Think that action would work for this project? The tikka has a single stack magazine that holds 4 down if I remember correctly. Would a single stack be easier to work for feeding the 470 vs a stagered magazine?

Sounds like something to tinker around with this winter.

Cheers

Jeffe-NFMike--Neck with a crush fit for
fireforming using the regular shoulder angle
that is same as other cases and probably will work. If not you can change angle later in same chamber to steeper, with another reamer,
I thinking about this case. The fact that you are shortening it means the area where the
shoulder will be will be thicker brass, so
there is a good chnce that the shoulder will hold headspace even if it isn't steeper angle.
I reccomend doing it with regular angle first,
after time spent studying it.Ed.

Hi Kman
It should be easier because you only have the cartridges entering the chamber one way. Straight on. Besides lowering the feed ramp it would also have to be widened on a double stack magazine. The cartridges will hit the side of the feed ramp and be pushed to the opposite side by the .475 bullet rather abruptly. With widening and lowering along with beveling the entrance to the chamber the feed issues can be sorted out. This could end up being a really good cartridge for people that want to enter the big bore zone. Like most guns you will have to modify other parts so it will stay together. Meaning the stock. I had a 338 Winchester that I had for years and shot lots. I rebarreled it to a 416 Taylor and the stock lasted about 40 rounds. You will have to take into consideration the stock quality and how is designed. By this I'meaning that Ruger for instance had the same stock design for their 30 06 as they did for a 375 or even 416 Rigby meaning the butt of the stock. They have changed that now but if your stock had a little butt area and a rock hard recoil pad you might not like it as a 470.
Re-enforcing stocks for big bores has been discussed afair bit on these forums. There are lots of experienced people putting input into Jeff's idea and he is a very competent and persistent fellow so this will come together.
Take care,
Dave

quote:

Originally posted by kman:

I have a 7mm rem mag on a __________...

I think Paul H is laughing every time he sees one of us make this statement...
( I believe I've read the 7mm isn't one of his 'favorite' cartridges, so the donor action being a 'Big 7' must be somewhat amusing )

Jeffe....what did you mean wih " Ross did it wrong and Rob had to fix it"?
Was Rob involved in the making of the Nyati?

whew..
rob, ed, paul, dave, neal.. and jeffe... either this thing will work or it will cause the end of the world when it's touched off..throw John into that, and it's all the monster daredevils

wish I could get all you fellas in a room, with a drafting table, no computers, and finish this one out.

For those thta don't know, Rob invented the 600 OK, Ed his line of hubel express, dave the 470 mbogo, neal the 550 magnum, i get an assist on the 550 express, and I did the 550 flanged, and paul is a great big bore nut!!.. oh, yeah, ed, john, and I are working on the 700 DA (Hubel short)

Ed's right.. the brass will be thick, but only .017" thick..

Anders told me that 26.565° allows for the same headspace gages. I am going to talk to dave manson on a "convertable" reamer, from 470 to 458...

Bent,
ross designed the nyati... and, for awhile, it was a one gun round (i know this feeling).. then some folks tried to make them.. and the simple fact is that ross's reamer design is incorrect.. his neck/shoulder of the reamer does NOT accomodate a correctly formed round. So, the reality is that the true blue nyati reamer needs a couple thou more clearance..

Rob analysed the problem when he built his nyati.. he, like a couple of the fellas mentioned in this entire thread, is just a little analytic!!! He designed a throater to clean up the neck/shoulder to allow the nyati to have correct headspace per ross's drawings (there's a conflict.. perfect brass won't fit a perfect chamber).. only slightly short headspace d brass actually fits a "perfect" chamber

So,
on the shoulder angle.. anything from 26.565° to 40 probably will work.. So, i'll talk to dave manson .. he's probably done more reamers this month than i'll see in my life...

jeffe

quote:

Originally posted by 470 Mbogo:
(sic)

PS that $1500.00 or $500.00"s more will put you in a whole different world.
Take good care,
Dave

Fair enough, but I figure if I'm going to the expense of going with a larger action, why not go with the 500 A2, or a 550 mag?

I don't mean the 470 AR to in anyway take away from your 470 M-bogo, the AR is designed to fit a different niche, one that likely doesn't need to be filled, but what the heck

Paul,
I think Dave think's this will work, but is asking us to be careful to not get hurt.. but i'll ask him over a whiskey in a month!!!

the 470 mbogo is the best AAR DGR i can imagine.. excellent bullets, downrange, and stopping...

and I want one really bad...

and I've got this RSM in 416 rigby that's a rebore away....

BUT..
there's a call for an AR round...
it SHOULD be a DG round... 470 is as classic as it gets
and I can get a ruger in 7 mag reasonable..

so, rum brass and a lesser 470... cool..

working on final draws to send to manson

jeffe

jeffeosso...when you get a chance...know you are busy right now...

will all the a.r. carts work in a b.l.r.?

will someone make the brass for us who are not so experienced in shaping brass?

glad to see the rolling snowball gathering speed

just caught myself daydreaming about what a 416 nosler partition in an a.r. b.l.r. would do to any animal...save buff rhino ele (they need 370 gr north fork )

http://www.northforkbullets.com/416-370.htm



s.d. .305, expansion around %200 weight retention %99-98...NIRVANA

Boomstick I've seen a 416 Taylor on a BAR. That would be some kind of fun.

Hi Paul,
I don't have any concerns about the AR470 and the 470 Mbogo. The 470 Capstick was out there before I woked out the Mbogo.I just want to help with some of the details so it is all figured and thought through. You have to let everyone know what datails have to be taken care of to make it work with the actions your talking about. I don't think it will be just screw on a barrel and there you go. There will be quite a bit of smithing required which could be expected to feed reliably.
Take good care,
Dave

Dave,

I do agree that there will be more work than a simple screw a tube on, life would be nice if it were just that simple. I'm optomistic that in addition to the new barrel, feed work will be minimal, but I won't bank on it.

quote:

Boomstick I've seen a 416 Taylor on a BAR. That would be some kind of fun

mbogo dave...you are a wildcating genious...

with that out the way from my understanding you cant hunt with a bar in africa and i would rather do the lever action thing. just makes the cowboy in me happy

Hi Boom stick,
What about the 450 or 500 Alaskan on I think it's a Winchester model 71 lever action.
Take care,
Dave

dave... did you mean the 50 alaskan? the 470 458 or 416 a.r. would be a real undisputed african cart for a lever gun. i have not hunted africa yet but hope to on my 40th (8 years and counting) would love to have one of your 470 mbogos when i go your creation has a lot of respect here and i think it will be the next 458 lott...just give people time to catch on

quote:

Originally posted by jeffeosso:

Bent,
ross designed the nyati... and, for awhile, it was a one gun round (i know this feeling).. then some folks tried to make them.. and the simple fact is that ross's reamer design is incorrect.. his neck/shoulder of the reamer does NOT accomodate a correctly formed round. So, the reality is that the true blue nyati reamer needs a couple thou more clearance..

Rob analysed the problem when he built his nyati.. he, like a couple of the fellas mentioned in this entire thread, is just a little analytic!!! He designed a throater to clean up the neck/shoulder to allow the nyati to have correct headspace per ross's drawings (there's a conflict.. perfect brass won't fit a perfect chamber).. only slightly short headspace d brass actually fits a "perfect" chamber


jeffe

Thanks , Jeffe!
Is Seyfried aware of this? Or does he walk around with the original?

Bent,
Ross is both aware and has retired his 585.

jeffe

quote:

I do agree that there will be more work than a simple screw a tube on, life would be nice if it were just that simple.

Paul,

This might be a really dumb question, but I don't own a RUM, or have access to any cartridge drawings...wouldn't you have to open the bolt face on a 7mm Rem Mag donor action too? I thought the RUM case head was bigger than the H&H case?

Or, when you guys say you're fixing up a 7mm Rem Mag (which BTW, I dislike too ), are you actually referring to a 7mm Rem ULTRA mag??

Cheers,
Canuck

Chris,
the rum is a .530 boltface.. same as the mag (527 or 528) and generally requires no boltface work from RUM to match HH mag

jeffe

Thanks jeff! Felt like a tool asking the question, but was not sure. Knew the rim was rebated on the RUMs but didn't know if it was all the way down to H&H size.

My buddy is potentially interested in converting a M70 .375 H&H to 470AR. Once you guys get 'er all ironed out, I'll let you know if I'll do one for him.

Cheers,
Canuck

CDNN is selling Model 70 Safari Express rifles in 458 Win for $899. What do you guys think about using that rifle as a starting point and re-boring to 470 or just re-chambering it for a 458 AR?

Forrest,
I think it would be awesome to just rechamber... i've for a winmag barrel on the way that will a victim of the same

jeffe

quote:

Originally posted by jeffeosso:
Boomstick
I'll print my drawing, then call dave manson about the reamer and headspace gages ($225)

then dave davidson on dies...(~$200)


I've already got a pacnor #6 475 barrel ordered, and I am getting a ruger mkI 7mag...

"where will the donations go?"

The reamer and headspace gages will go to pacnor for the rest of us to have access to, and not have to spend $200 bucks for access!!! Pacnor can mount your barrel or deep chamber it.



If ya'll want, they will do a discount for an order of 5 or more of the same barrel.

A guy could then get a $400 action (high, but let's talk). order a necg front sight, a barrel band, and a williams peep sight ($150) send to pacnor for gunsmithing, $600.. and a set of dies $200

$1350, assuming the stock will work...



jeffe

Sounds great now let me see. ???

A used BLR in 300 win mag ??? a ..Wait..
uhh i guess i would just need the barrel then is all and transfer the sights from one berral to the to the other .. cost ..under $900.

As with the .550 bullets .. pottsy will have it done before you Na Na Na Na

Martin

PA Bullet's

quote from jeffeosso...

Paul,
wow..

cover's lefty's
the 7 remmag problem
lever DGRs (if you GOTTA have a 45 for a DGR, make it a 458 A.R.)
and cheap brass...

LMAO...

excellent work .. see, i new there was a reason i was sharing the blaime... er credit, for design with these

jeffe

we band of bubbas

end quote.....................................

potts...got jeffe to admit to the d.g. lever rifle

quote:

Sounds great now let me see. ???

A used BLR in 300 win mag ??? a ..Wait..
uhh i guess i would just need the barrel then is all and transfer the sights from one berral to the to the other .. cost ..under $900.

As with the .550 bullets .. pottsy will have it done before you Na Na Na Na

Martin

martin...are you trying to have the first africa lever gun and beat jeffeosso to the punch?

quote:

Originally posted by boom stick:

quote:

Sounds great now let me see. ???

A used BLR in 300 win mag ??? a ..Wait..
uhh i guess i would just need the barrel then is all and transfer the sights from one berral to the to the other .. cost ..under $900.

As with the .550 bullets .. pottsy will have it done before you Na Na Na Na

Martin

martin...are you trying to have the first africa lever gun and beat jeffeosso to the punch?

To tell the truth.. i thought i already had/have a few DG rifles... my 50-110 BLR
525 grain jacketed bullet 2300+FPS
My bolt action Ruger M77 458 win mag..
My 35x378 Weatherby both my 9.3x64's
to name a few... Ohh wait .. you mean "another"
DG lever action "like" my 50-110 Na i will let jeff get there first with the new AR rounds ..
its his baby let him run with it .. if it works out the way it looks then ya i will have one made up on a BLR Just so i can send it to
700 Nitro lol We all need a fun gun ..

Martin

Paul,

The shoulder on a loaded 411 cartridge case measures .454 and my die was set to crush fit the case into the gun. I've had no problems with headspace on this gun.

I feel the 475 AR will be great.

I've got a Winchester Boss, 338 Win Mag that I'll send Jeff's way if you want to use it as a test platform for awhile...

It's got decent wood, but would need crossbolts installed and the barrel channel opened up obviously...

When you are done playing with it, I'll screw on one of the 375 AR barrels

Jbabcock, et al,
I'll be calling Dave Manson to follow up.

I received my 22" 458 winmag mauser barrel today.. that will become the 458 AR...

still rooting around for my 416 AB barrel.. i KNOW it's in the shop..

and the 470 barrel is on order for the ruger

I am thinking this is going to be a fun project

jeffe