We today was the first time I broke 2200fps with 700gr jacketed, then 2250fps, then 2300fps, then 2350fps, then stopped at 2372fps @ 8750 ft/lbs of muzzle energy. Needless I am very . Recoil was still very surprizing low.

RNS

Neal- Those are some mighty fine numbers! Congrats my friend!-Rob

neal,
you ROCK!!!!

jeffe

RNS, that is VERY impressive!

Neal,

Great, just great! Keep the reports coming. I need to call Mike and talk timelines and send him some more money

John

Neal-Was that all with W-748 and how did cases extract.Glad you got gun set so it tames
recoil.Oh what is your barrel length.Ed.

Given that a 460 will do over 2500 easily with 500 grain bullets those ballistics on the 550 are what would be expected since you get a percentage increase in kinetic energy equal to half the percentage increase in bore area, assuming equal pressure and equally suitable powders.

Mike

Thanks guys

The barrel is 26" and the cases still extract like butter. Out side temp was 85 F in the shade and 120 + surface. We were shooting clay piegons at 100 yrd off hand and then some from the bench and accuracy was putting several shots in one ragged hole if I did my part. It does take a little getting used to but I am surprised after three or four range trips I am about 90% used to shooting it off the bench and off hand now is fun smashing large rock into small rocks. The powder was not 748 it was ???? notes are not with me right now. 760 will be my next powder.

RNS

By the way shooting the hawk bullets 700gr .035" jacket. I know that they are not bonded and jacket seperations can be expected but I have yet to recover a seperated one. I recovered about 8 from smashing rocks and shooting through a steel tire rim I had nice round hole through both sides with no seperations. They are tough enough for any non dangerous game that walks. I would still prefer the bonded cores though.

RNS

Hey Neal that's great news. It sounds like your having too much fun. I guess that hogs in Nov is a for sure item.
Take care
Dave
Mike I think you will find that you gain 25% not 50 % of the differential in either case volume or bore gain.

Dave,

Half the increase in "bore area"

The 550 has 44.2% increase in bore over the 460 so would have 22.1% increase in KE.

Mike

Hi Mike,
Are you refering to the John Barnsness (spelling) article written 5 or 6 years ago. That's the one I've read where he figured a 25% gain based on the difference. If you figured the 550 and the 460 Weatherby you would have to take into consideration the 25% gain on the powder volume difference also. So if the case had 8% more powder cpacity you would realize a 2% gain in performance at the same pressure. I think this is very realistic.
Take care,
Dave

Dave,

The percentage increase in velocity being a quarter of the percentage increase case capacity, I don't know where I originally goy that from. Have just seen it several times.

The increase in energy being half the increase in bore area came from some physics.

Actually in practice necking up usually results in a slighly lower gain and there seems to be two reasons for this. Firstly, calibres with bigger case capacties for the bore size seem to retain or develop peak accuracy at higher pressures. In other words if we load a 308 and 300 Winchester to the same pressure then the velocity difference is "x"

But if in bench rifles we load then both to the point where accuracy falls then the velocity difference between the 308 and 300 Win will be greater.

The other issue is that necking up often results is less net case capacity with big bullets being used in the larger calibre.

Mike

RNS, you're a sissy.
Take it to 2400 fps and get back to us.
[Wish I was near you and could "help!" ;-)]

Neal,

Excellent results! Can you give us more loading info as to the powder and charges you are using?

Doesn't Hawk make bonded core bullets these days?

MAN

Lets see the 585 Nayti, the t-rex, the 600 nitro, the 600 OK, and the 700 Nitro are really the only thing more powerful that the 550 Magnum and I still get called a sissy. Just when I was going to run with the big dogs someone goes and kick me back to the porch.

RNS

RNS--I think your case will beat the Nyati, give T-rex run for the money when you get her loaded all the way up. You ain't got no shoulders to
soak up energy, and brass is so much better
and tougher.Keep blasting, the only way t-rex will beat us is with sticky cases while ours extract easy.Ed.

The 585 NYATI will push a 750gr bullet to over 2500fps. However, I can't imagine a WORSE case design. The .600OK will drive a 900 gr bullet to over 2400fps. Now of course the 12GaFH will drive a 1000gr bullet to over 3000fps. I too just love those straight wall cases. Neal -Watch out for excessive belt expansion and loose primer pockets. Thats what determined the limit on my 500A2. I never had any sticky extraction. -Rob

Rob was your A-SQ using A-Sq made cases or converted Wea(Norma) cases. We may do better with 550 if non A-SQ brass is involved.
I think the non A-SQ heads might hold
pockets to size better.If so breaking 2500 with
700 gr will be possible.Ed.

Good! Very Good! I shot my .50 Alaskan single shot with 700 gr. hard cast lead (my own cast bullets) with a copper .50 gas check at 1750 fps.
That rifle was only 7 pounds...lots of muzzle rise but recoil not bad at all. So, I'm not surprized
at your comment about recoil & I'd assume more weight than a 7 pound rifle.
I'm trying to research info on a rifle cartridge made up by the famed Chas Newton who was said to have made...now get this...a .450 caliber rifle shooting a 500 grain bullet at ...3,000 fps!
Move over .460 Weatherbys & make room for the KING!! Any info published was in a Canuck (sorry Canadian!) publication...any Canadians out there contact me via this site & help me find the old info!
"Illigitimi Non Corborundum"!
Best Regards, Tom

Bison-My 458 will do that with hard headed
BB cases, but case life is about 3 reloads.
So I never pushed loads like that.
I wonder what brass he used to get that.
Nice thing about 550 it will get same
energy level and brass will last a while.Ed.

The great Ross Seyfried designed the 585 Nyati.Cant imagine why RGB thinks it is such a bad design,maybe it is because he did not think of it first.ROb you are what I call a gunsnob,since you post your opinion so freely I am exercising my right to post mine.Just so you know my old handle was the "dieseldude" so I am not new to the forum.

Ross is great, but cases are not as the
problems all the brass makers made into
the damn things screwed them up, which would have been harder for them to screw up, with
a different design.Necks wrong thickness, bases off center, hardness wrong,bases different sizes, and so on.I
have 7 types on hand, so I know.Ross made first ones on lathe from 577, and I think they are the only good ones.That is the reason we like
the 550, so much more brass that is uniform'and no shoulders to worry about...Ed.

quote:

Originally posted by Robert Childers:
The great Ross Seyfried designed the 585 Nyati.Cant imagine why RGB thinks it is such a bad design,maybe it is because he did not think of it first.ROb you are what I call a gunsnob,since you post your opinion so freely I am exercising my right to post mine.Just so you know my old handle was the "dieseldude" so I am not new to the forum.

DD,
the problems with the nyati are
1: severly rebated rim (causes feeding issues)
2: the neck/shoulder PRINT calls for this area to be too small, and requires either that you push the case shoulder back when forming cases OR your get another (properly) designed reamer.. that would be designed by rob

If the nyati wasn't rebated, and the shoulder was drawn/executed correctly, it would be a "decent" round... in fact, it would be the 577 trex... which, other than being HUGE art did get right.

the 550's don't have any of these issues... the case head will fit on a mauser/cz/riger/etc
brass is cheap....

cases properly designed, vetted, and approved...

Remember, now, the great ross (and i agree) is STILL a gun writer.. which means from time to time he can use his special 24" "yard" stick, and his handidany 11oz "pound" with his 7.5" "foot" tape measure....

fact is the 550s are simple (i like my word.. chimple) to make... and theres more brass than bertram for em!!!

jeffe

Not my intention to downplay the 550 mag or the 600OK,both are great cartridge designs. Thank you for the explanation of the case design on the 585 Nyati. I know guys out there that have them(585) they seem to be just fine once the bugs are worked out.

DD,
the bugs working out, is really the case in the nyati.. rob's redesigned reamer works well... and then it's just a feeding issue,,,

btw, it's a HOOT to shoot, the nyati!!!

jeffe

Feeding with the .585 Nyati is not an issue if the rifle is built by a competent big bore gunsmith. But there are few of those. I would bet that not more than 20 gunsmiths in the USA could get a .585 Nyati to feed properly.

Bertram brass sucks, but you can get good .585 brass from Horneber.

As for the shoulder of the .585 Nyati, I never had any trouble with it. The reamer that Pac-Nor uses does not open the chamber enough in the neck area, so I had to neck ream the chamber. But that was not a big deal, since it was a custom gun anyway.

The .550 is an excellent design, but the .585 nyati is a good design when competently executed, kind of like a muscle-bound .500 Jeffery.

The one achilles heel of the .550 mag is getting mainstream bullet makers to produce a continuous supply of bullets.

Dan,
hawk, alaska bullets works, north fork, 2 solids, and cast bullets... why, that's exactly the same choices as a .585 bullet, right?

no, wait, barnes just came out of a .585 XLC bullet... we need THOSE!!!!

as the reamer was wrong for pacnor, that had to be fixed before feeding could be worked on.

The issue with feeding is EXACTLY what you said... i doubt there's 10, not 20, that can get an nyati to feed flawlessly...

a barrel plumber could screw a 550 barrel into a weatherby 460, add the extended mag bottom, and voala, 3 down, feeds perfect. SERIOUSLY

jeffe

The main bullet that is missing from 550 as compared to 585 is the Woodleigh.

But ease of converion and brass are the big points in the 550s' equation.

The 550's smaller case will always make it a better proposition for reduced loading.

As to power, while the 585 and 600 OK can exceed the 550's power level I think that the 550 can already exceed the recoil level that can be used in a normal rifle and where the rifle is actually being used as opposed to a few shots into tins of water etc.

Personally, I think the 600 OK virtually eliminates the 585 Nytati from consideration as the 600 OK is at the top and maximises what could be done with normal sporting rifle size actions. The 585 lacks that pizzaz factor and it lacks the 550s practicality.

Mike

Mike,
you are dead nuts on!!

if we had a 700 gr woodliegh solid/soft and a barnes XLC (about 625 gr) this would be PEFECT..

you are also perfectly correct on recoil level..

I dont know where in oz you live, especially compared to woodliegh, but if you could ring up Geoff and have him run a batch!!!!

jeffe

jeffe

The Australian Karl who posts here go McDonald to a run of 900 grains in 585, as I remember.

But of course that is the same calibre.

I think McDonald has already been through a version of the 550 himself and I think he called it the 540 McDonald express. So he obviously had a little more taper than the 550.

Woodleigh is in the southern part of Australia which is where you also find Bertram and that part of Australia is also where you find all the double rifle shooters, 404 Jeffery people and so on.

There is a club in Australia called The Australian Big Game Club. If you had a Weatherby or a Browning A bolt you would be expelled from the club. If you had a Weatherby or Browning A Bolt and were using Hornadys you would be hung from the nearest tree.

That part of Australia also has our gunsmiths that are most likely to me making 404 Jeffery, 500 Jeffery etc. in thumb cut Mausers etc.

If you go to the forum NitroExpress.com there is a poster there (he is on AR as well I think) called 500 Nitro. He has an original 505 Gibbs. He also use to bring in Bell brass to Australia and he also was/is (not sure of the current status) invlolved with Woodleigh for organising distibution of Woodleigh bullets to Australian gun shops. So perhaps he is the man to start with on lobbying Woodleigh for 550 bullets.

As a side note you don't find Woodleighs used much in Australia by 375 and 45 bore shooters, tends to be Hornady, yet big bore Hornadys cost much the same out here as Woodleighs cost us.

Mike

Mike,

As for Geoff McDonald/Woodleigh, he built a 530 on the 460 Wby, then, the 505-530 Woodleigh. the Gibbs opened up tho .530".

Hog Killer

Hog Killer

I thought it was 540, must have been thinking of 340 Wby at the time.

Did not know he did the Gibbs on the same calibre.

I think getting him to do anything different these days like 550 bullets would be close to impossible. For example, they will no longer sell their bullets direct to Australian shooters and someone told me a couple of weeks ago that even enquiries are answered with a "talk to the gunshop" etc.

Mike

Mike,

I found that info in, 10th ed. "Cartridges of the World". It's in the back, the chapter is on developing wildcats. If Geoff is still trying to push a .530 cartridge, he may not want to do a .550 bullet, as it would top his, in size.

It is a shame that Woodliegh has changed their policy on direct sales to you in OZ. As small of a market as there is down there, you would think that they would do everything posible to get as much of it as they could.

Hog Killer

Hog Killer

It is quite stupid because most gunshops don't have Woodleighs. However, most dont carry 375 and 458 Hornadys. HOWEVER, they are dealing with the Hornady agent on a regular basis because of the Hornadys, Leupold scopes and mounts etc and etc.

But he must want some of the market because he did introduce some non boned quick expanders in 30 calibre. He also makes a 400 grain 45/70 bullet but I never at the range seen anyone using it....always bulk Remington 405 grainers, 400 grain Speers and 300 grain Hornady and Sierras and ditto for 458 Win shooters.

The Australian bullet maker that gets the business is Taipan. One reason is they make down to 224 and they make quick expanders in 375 and 458. I have been told that their 416 is a quick expander as well. I don't like 416 because of lack of bullets as compared to 375 and 45 bore size. I did have a Rem 700 in 416 Rem and also a 416 Wby just to try them. Of course if you were to use the rifle only for genuine big game hunting then 416 would be as good as 375 and 45 for bullets. Early on in the peice Hornady were going to bring out a 340 grain spitzer in 416 but canned the idea.

As a side note, I found with 400 grain Hornadys the 416 Remington to be a better thing than the 375 for powder. 2208/Varget was spot on but is a bit fast for the 375 and the 4350 burn rates a bit slow for the 375.

The Reminging factory ammo with 400 grain Swifts did just over 2400 on the Oehler and I was able to load to 2500. This was 10 years ago so factory ammo might be different now.

Mike

Price wise the Remington 405gr/45-70, bullet is really hard to be, as I can get them to the house for about .15ea. I am using them in my 458 Lott, for plinking and will use them on hogs with a reduced load.(1900fps). I plan on also using them in some 45-70 loads too.

Hornady will probably get most of my other business for feeding the Lott. When I want something better to use. If I every get to go to Africa, I think North Fork Will get the nod for solids and softs.

If I was to load for any of the classic NE rounds, then Woodliegh would have a good chance, as they are really new Kynock bullets. They worked then should do just fine now.

Hog Killer

Agree. If I was down the 404 etc path I would load Woodleighs. But if I had a 404 I would even want it in a thumb cut Mauser.

I know there are few on the forum and are nice looking guns but I just can't see the 404 type stuff in Model 70s.

But given I am down the Weatherby path the chances of the above happening is very small

Mike

I agreee that some combonations work and some seem closer to a sin. Like a 460Wby in a SxS.

Hog Killer

If I had the money to waste I would get one of these in 300 H&H and one in 375 H&H. A mate of mine reckons H&H would take legal action.

http://www.weatherby.com/_images/products/rifles/_enlarge/ctm_crown_big.jpg

Jeffe,I have some 750 XLC's,matter of fact went out a nd tested them today,despite the wind and rain!! I loaded 125 grs of rl-15 which gave me2033 FPS,they shot low,which I figured they would,recoil not bad! BTW this shooting was done off the bench!!!! between shooting my 375 rum. I will say it was a perfect day for working up a load,with the rain and wind.GOt a black bear hunt in May going to take the 577!!! still need to get those XLC's to regulate!!!