To those interested I thought I would change the name to 550 mag since I can't find any information on the 550 Ivory Express and it is most likely someone elses brain child.

The 550 mag is a 460 weatherby necked up to .550", bore dia is .540" and grove dia will be .550". I am trying to find some weatherby basic to form the first cases from. I have talked to Dave at C&H Tool and die about the reloading dies, and at his request David Manson about the reamer. Both have no problem and have offered to help as they can. Bullts weights should be 600 to 700 grains and I have no Idea of what fps this will do. I wanted this to be an easy conversion with a easy supply of brass.

The barrel will be the hard part if I get BTAF approval. Pac-nor has said they will do the barrel the tooling costs will be about $1,000.00 and barrels will probably close to $300.00.

Another option is Wells sports store which Dan also said they could do a barrel, there cost is they same $1,000.00 for tooling and $300.00 for a barrel. Wells will fit the barrel with integral recoil lug to the action chamber and make sure feeding is prefect also for another $350.00 http://www.cutrifle.com/barrels.html check out there web page. Reamers should run between $150-$200 add another $650 or so for a cz-550 mag, ultra mag or PH from Montana and we have got a barreled actions.

Quality cartridge, Mast(Bell) brass, and Buffalo arms are out of weatherby basic. SO WHERE DO I FIND SOME?????????

Well to do the math that is $1,300.00 for a barreled action another $200-300 for a stock and you pick the rest like sights ect.

Check Huntingtons for cases.You shouldn't need
approval for a sporting cartridge barrel.

Don't make reamer till brass is done and with
your straight chamber, have reamer .050 longer,
so it cuts down trimming.Ed.

RNS

I am fairly sure that Geoff McDonald (Woodleigh bullets) had some he called the 530 or 540 McDonald Express. I guess it will bea 460 Wby taken out as far as possible, sort of a fattened up version of the 458 Lott.

So he might have already paved the way for you. I wonder if had to worry about where to obtain bullets

Would it not be better to neck up Norma made 460 cases?

Mike

RNS- A CZ550 action should be no problem at all to convert. I've had super results making 500 A2's out of 416 Rigby's and since your using the same case, it should work just as well. Don't use the .375 CZ action as it will take much more work to accomplish the same thing.
Man at $1000 for tooling costs that sure makes the .600 barrels look like a bargain! Given what I think this case would look like when opened to .550, you could get by with using a stock 500 A2 reamer and a custom neck reamer/throater. This way you could set the neck as long as you wanted. I would get John at Bridger Bullets to make you some slugs. Best of luck!-Rob

Rob-It is a great plan, headspacing on the
belt only, like your 600 OK. 500 A-SQ neck
now measures .536, with .040 in bullet diameter
added it is .576. WEA base is .582 ahead of belt, so it is easy to use belt. Which actually makes reamers easier to build.I run some info through my formula I posted below and with decent
length barrel, 50K psi ball-powder load and
he will get little over 2500 fps with 700 gr bullet..10,000 ft lbs.Ed.

This is one of my modified wildcat cartridges on the table. It would be better to have a slight taper and a parrallel neck so a 54 caliber would be the larger I would go with the 460 Weatherby casing. My original wildcat was in 53 caliber but it was still in the concept stage. Thanks.

They're charging you $1,000 for tools that they'll keep and use?Yeah,that sounds real fair.

Brian.

Not to dampen the fun, but a custom bore size is gonna cost you. When you figure the cost of the barrel and tooling,ream,er and guages, reloading dies, action, gunsmithing, stock etc. your gonna be in the $3000 range. A very good 500A2 will cost less than half of that and is capable of launching 700 gr military .50 ball pulls at over 2400 fps. You also have to figure out exactly what twist you need to stabilize a 700 gr .550 bullet. In the end I deceided to stick with std bore sizes and stay away from custom/non-std bore sizes due to the unreal costs involved.- Rob

Ming
Thanks that is almost perfect I will let you know the final dimentions

Rob as normal you hit the nail on the head. The orginal Idea came when I had a 600 OK next to a 450 watts case and it looked like something should be in the middle. So I put in a Weatherby case and bingo the middle was filled. My first thoughts were to do a simple conversion take a 416 rigby put on a new barrel with a bigger hole. Everything was going ok until that $1,000.00 bite me in the rear where my wallet sits. Which is really what drives the cost of the first rifle up.

The reloading dies will cost the same as my 450 watts. Brass the same as the other weatherby rounds. Gunsmithing the same as any other rifle. Reamers and go guages will cost the same as any other wildcat. You know and so forth, but that $1,000.00 is the line that most won't cross and I my not either

I did email John about bullets wait who is planning this me or you . So with supplier of bullets and the barrel in .550 there are other cases that could be had with a .550 say a .550 gibbs with good brass from horneber. With all the large actions down the road it makes it all the more fun to dream about.

I got the answer I need to loose a few pounds so I wonder how many lunches it would take to pay for the tooling. Any way thanks for responding and I will work on that $1,000.00 part. RNS

ED
Those figures are shocking never thought it could get that much.RNS

RNS- Mingo--Rob--I am interested in this caliber
as an upgrade for my 510 HE. I have a barrel
already in 50 cal and would get it bored, have a
550 HE on my 3.8 inch cartridge.I would be willing to pay for part of tooling if 3 others
joined in. Maybe more from the forum also.Like if ten got together it would only be 100 bucks ea.
But I will join in if 3 others do.And then each could buy barrel or in my case rebore as long as who we do it with can ""rebore"".Thats important.
As for the case if using 460 brass, which is best as using 510 A-SQ the brass is sometimes thin in base,the neck would end up about .570(.550 plus
.020)...You would have a real straight case so
that the sides are parallel enough.You would
only have 1 thousands taper in the length of the
bullet seated in case.Just a straight side.Ed.

I suspect the tooling would include the cost of a custom made .550 deep hole coolant fed drill and a new carbide rifling cutter. The button for the .600 three groove barrels was about $300 as I remember. I don't even want to think about a deep hole drill. It brings back memories of my experiences making a muzzel loading rifled barrel myself! Bad Idea!-Rob

Rob-I talked to two and will talk to more as these were months behind.They said that deep hole drill,finish reamer, rifling cutter was what they would have to make for about a grand.They were
cut rifled barrel folks.What is the bore diameter
of a 55 cal Boyes rifle. and does anyone make barrels for them??Ed.

You guy are reading my mind now Ed is doing it I was wondering the same thing about the .55 boyes. If we are lucky the grove will be .550 and if we are very lucky the twist rate will correct if the .55 boyes was shooting about the same weight bullets. I was going to start looking through my last copy of Shot Gun news to see if I could find a supplier of barrels.

Ed I called Cut rifles and was going to ask Dan if they could rebore a barrel. Dan was out of the office and Fred Wells answered the phone and said it should not be a problem, but check with Dan to make sure.

[ 03-27-2003, 03:27: Message edited by: RNS ]

RNS-I "think" the Boyes groove diameter is bigger than .550. That is why I asked.How quick could Wells get tooling done and be ready to build barrels.I am in no huge hurry, but don't want it to take a year.All I have to do is run expander in my 500 HE case and instant 550 HE.I already have expander, and very little work to make resizer,And like I
said we will help.And with John able to turn out great bullets, at great price that solves that
aspect of getting it done.Ed.

Ed,

This is some data that was posted a while back in response to a question I asked about the 55 Boyes.

Extract from "Cartridges for Collectors, Vol 2 - Fred A Datig"

.55 Boyes Anti-Tank

Bullet diameter: .562"
Case diameter - neck: .604"
Case diameter - Head: .793"
Case diameter - rim: .800"
Case length: 3.888"
Bullet weight: 926 grains
Muzzle velocity: 2500 fps
Belt: .851"

Hope this is what you guys were looking for.

Axel

Everybody including me used to rebarrel the Boyes to .50 BMG. Talk to Kent Lamont he probably has some .55 Boyes barrels left in his shop. I'll look around and see if I have any if so, they are yours for free!
Axel- There are a few guys over on the gunsmithing forum dissing your work over at Arnold arms. You better reply big time to the assertions that your gunsmithing was all done with a Dremel toll and Unimat! I still don't understand how you made a Cone with the trusty Dremel?-Rob

[ 03-27-2003, 08:20: Message edited by: Robgunbuilder ]

Rob-With a bullet dia of .562 it would be too
big with case neck thickness from Weatherby case adding 20 to 24 thousands.Be bigger than the base
meaurement of .582.Rob I could use those BOYES
barrels for reboring for my bigger cartridge
testing; and will trade, if you can find them,
some brass for you to build 12 GA From Hell.Ed.

hubel458 = axel ???? hmmmmmmmmmmmmm?!

Kmule-Why don't you join in and help.Shooting,
reloading,wildcatting, are great. And working with others in these hobbies, allows a lot
more to be accomplished.Ed.

Rob,
I could use a boyes barrel or three!!

Axel's back? hmm, where's that rifle he promised would be done before he'ld come back... somethign about "you'll see"

jeffe

Jeffeosso, Since you asked. The 22 DGR is out to be blued. I subcontracted the bluing operation out. Too much expense for me to incur, since I do not blue regularly. Next it will be restocked. I expect to get the rifle back late May from the bluing company. I can get pictures when it come back. It will not have the new stock yet, however. Do you want pictures then or when the rifle is complete?

I have not started on the big bore yet. I am currently thinking of building a 458 Win Mag or 460 Short A Square on the M70 I bought. I haven't decided yet. Although, I haven't ruled out a 585 Nyati, either.

Axel

Ed- I wasn't even considering the use of a Boyes barrel on a 460 WBY case. I was just commenting on the Boyes barrels.I'll look in the attic and see if I still have any Boyes Barrels. -Rob

[ 03-27-2003, 22:24: Message edited by: Robgunbuilder ]

I found out that Horneber can produce weatherby cylinderical in june (approx) That would be great for me.

RNS--I annealed a 460 case and used expander on it and put in a 550 cal brass bullet I made,
to give you a view of what it would look like.
On left is 30-06, center is 458 WIN. and then your
550 Magnum. Hope Mingo likes it too.Looks great. We get a bunch of big bore nuts interested we will get it done.And that Cal will work great for my long version also.Ed.

Ed,

Looks mightly impressive, like a 458 Win mag on steroids! If the barrel cost would/could be brought down I would be interested in one of these instead of a 585 Nyati.

Has anyone done the math? The picture suggests the 550 is a scaled up 458 Win mag. Just like the 50 BMG is a scaled up 30-06.

Axel

RNS,

I have updated the drawing and this is the latest and greatest. Let me know if you would like to change anything. I suggest to have a parrallel neck for a maximum grip on the projectile. Thanks.



[ 03-30-2003, 06:34: Message edited by: Mingo ]

Ming the drawing looks great you have a good idea about the neck and you probably won't be able to see it since it is almost a straight taper. I think if Horneber makes the cases 3.00" like I requested I will just make the neck .600" insteat of .500" that way the body and neck point will stay the same and one can shoot a formed case or use cylinderical.

Ed the case looks better than I thought it would let me know if you get tired of looking at that case and I will be happy to look at it for awhile RNS

Ming
How did you determine twist rate??

A 1/18 twist would be plenty. Only need 6 grooves, they are only using 3 grooves on the
600 OK..Ed.

Ok so we have three people interested and some more details to work out. RNS

[/URL]

RNS,
Here is the 460 basic drawing you requested. Please keep me posted on the progress. As for the twist, I pulled that out of the A-Square manual. I like a faster twist because I like to shoot a big and heavy bullet at a moderate velocity. Actually for a cartridge this big, I have no desire to shoot a 600-grain projectile faster than 2100 fps. Thanks.

[ 04-07-2003, 01:23: Message edited by: Mingo ]

Ed,

Thanks for the picture. The 550 cartridge does look impressive and it should be as wildcat as it's gonna get. Sorry I don't think I can get into this deal with you guys at this point. Got to set my financial priority straight or I will have to rob the bank one of these days. Keep up with the good work my friend. Thanks.

[ 04-10-2003, 08:11: Message edited by: Mingo ]