I have emailed Rob but since he is away for awhile I will post my questions here. Can brass be turned from solid bar stock? If the brass issue is this simple or can be solved I'm in. I've got a 500a2 project I'm finishing up and this would be a great one to follow it. Can the bullets be turned from a standard brass/ bronze rod?
Thanks, John

500, your a Nyati owner how much gain do you think we will have over our .585's with this .600 ??

What I mean is it is a large enough increase in bore size in our collections over the .585's to make it worth it. My idea would be the ideal jump would be to .700 what ever. The only thing is the action becomes an issue. For what it would cost me to do this rifle for an extra $1200 or so for a bigger action I could have a .700 built. What action does one require for the .700 (brand).

PC,

If the case capacity was the same and they were both loaded to the same pressure and with equally suitable powder, then the .62 calibre would give a 6.3% increase in energy.

So lets say your 585 does 2450 with 750s then 62 calibre on the case capacity would do 2525 with 750s or 2300 with 900s.

However, I assume this is a larger case.

Your velocity gain with an increase in case capacity will be about 1/4 of the percentage increase in case capacity. In other words, if this case is 20% larger than the 585 case, the velocity of 2525 with 750s and 2300 with 900s would be increased by about 5%, that is, 2650 for 750s and 2420 900s.

Should be extremely pleasant to use on a winter's night out west while spotlight shooting

Mike

Yeah this .600 looks like it will make my .585 look like a cap gun

And would be just the ticket for whistling in pup foxes. When the start charging toward the whistle it's imperative you are armed with a true stopper

Fritz,

It is possible to turn brass from solid stock. The problems with doing so are (i) expense, (ii) time consuming, and (iii) turned brass does not rebound as well as drawn brass.

However, Rob thinks that the Horneber fellow in DE will make .620 brass for us. So if we do a group order, the brass should not be an issue. It would be wise to order a lifetime supply of brass first time out, however. I plan on getting at least 300 rounds of brass. Maybe 400.

PC,

I expect to get 3 primary benefits from a .620 that will distinguish it from my .585:

1. Greater transfer of shock to game. Let's call it a bigger 'SPLAT!' when the bullet hits.

2. Larger wound channel, more rapid blood loss, etc.

3. A more manly looking round in my cartridge belt.

Realistically the 585 is more than is needed. A 500 A-Square fulfills my wildest dreams of horsepower, but I like the SPLAT! of the nyati and I think I will like the SPLAT! of the .620 even more.

It is also fun to hold up a .458 lott round next to a 585 nyati and observe how puny the lott is. Next to the .620, a Lott will look like a 22 LR.

For the .700, I think you will need a McBros action from McMillan. See the link.

http://www.mcmillanrifles.com/Accessories.htm

Click on rifles to see what they look like. They are a very large push feed action and are not elegant, in my opinion. Further, the .700 starts to lose a lot of penetration, and recoil goes up quite a bit. So the rifle would need to weigh in a 18 pounds instead of 15. I am hoping that I can handle the .600 with a muzzle brake at 13 pounds.

If not, then I am in for an awful beating.

500Grains,
The reason I asked is I have a couple of CNC lathes and could easily turn the brass myself thus reducing the cost. It is the strength issue that concerns me. I am aware that drawn brass will be stronger and exhibit better properties for long term use but if I can turn them, all I've got to do is program the lathe, load the bar feeder and let it run all night.
Thanks, John

Fritz,

I think it will work for you.

But at high pressure you might get stick extraction due to the rebound issue.

However, I doubt that any of us will shoot such a round at high pressure.

Would you be interested in setting up to duplicate the GS Custom bullets? I would dearly love to have some but I cannot get mine from RSA. They are not patented, so there is no legal problem in copying them. I could send you a sample in .458 and .474. My primary interest is in getting them in .366, .458, .474, .585 and .620 calibers. Norbert suggested using MS72 copper for home made solid bullets.

If you are not interested in setting up, do you know a lathe owner who is?

Thanks.

Sorry Rob and others....
- But I do not like the design of that cartridge. I don�t like the rebated rim at all and I also don`t think the belt is an improvement to any cartridge - I would prefer a proper shoulder any time.
But I wish you good luck with your project..

500grains,
I have done this for myself before and have considered doing it as a side line. Unfortunately my big concern is with liability. In this small comunity here is SW Montana the phone book has page after page of lawyers. I will put a call into my product liability agent just to see what the damage would be.
John

500,

or any who know, I have just about finished my .585 as some might be aware, now we have this .620 popping up and I am tempted to get a barrel, dies & brass and sit on it for a while. What I want to know is that before I started my .585 people were saying "The CZ/602 was on the verge of not being able to handle the .585" now we are going to build a .620 calibre rifle on 550's/602's and with the extra back thrust of the larger calibre than the .585 are we not going to exceed the capbilities of the lugs ???

How many shots does one get out of a .585 before the 602/550 action will fail ??

And how many will one expect to get from the .600 before action failure??

What do people think ???

PC,

I suggest having a look at an article written by Dan Lilja on bolt lug strength. The intro is below, and you can find the rest of the article on his website.

If you decide to do the calculations, let us know what you find.

A Look at Bolt Lug Strength

by Dan Lilja

All action designers are concerned primarily with producing a safe and functional product. All other considerations such as weight, finish, eye appeal and other cosmetics are secondary. From a safety standpoint, the strength of the bolt lugs is of prime concern. Bolt lug shear strength depends on several inputs. Some are fairly obvious, but others may not be at first glance. The number of lugs on the bolt is in the obvious category, as are the axial length of the lugs and the width of the lug. Or more precisely, not the actual width but the length of the radial segment of the lug that's connected with the bolt body. Also, the strength of the material is important.

The shear strength is calculated from these factors, as I will explain in detail a little later. This shear strength must be greater than the amount of backwards thrust on the bolt generated by the cartridge being fired. So another number that must be calculated is bolt thrust. Bolt thrust is fairly simple to calculate and depends on the inside diameter of the cartridge case being fired and the chamber pressure.

Also of interest, but not necessarily crucial to safety, is the amount of flex or spring in the lugs while they're under the thrust load.

So then, we will look at three different calculations related to bolt lug strength: lug shear strength, bolt thrust as generated by the cartridge case, and lug flex.

http://www.riflebarrels.com/

500,

I think I can do those calculations if given the figures such as "legth of arc segment" etc, inside case dimesnion etc.

Am I being ignorant in that the 550/602 actions caneasily handle the pressures of the .585 & .600

The action can easily handle the pressure, as these are not high pressure rounds.

The issue is whether the action can handle the bolt thrust.

Some forumites have questioned the wisdom of the 585 conversions on bolt thrust grounds. No one has done the Lilja calculations so we don't really know where we stand. Lemmings, all.

But so far at least I do not have a bolt handle stuck in my head.

I posted in the wrong forum earlier but why not use the BBK02 action instead of the CZ?

THe Ultramag is rough as a corn cob. I have an Ultramag and a CZ550 next to each other in the safe, and the Ultramag makes the CZ550 look like a Gary Fisher custom.

500 Grains I didn't know that. Live & learn.

Surely,

there is a mathamaticion amongst us who can derive the figures we need.

I am betting that action life is halved maybe more when shooting calibres usch as the .585 etc. I think it would probably be wise to have your action checked by a gunsmith every 500 or so rounds just to see know damage is done. Obviously most can not handle 750's at the velocity's that the .585 can produce. It seems like 2100-2200 fps seems to be the norm, this would help action life as bolt thrust would subsequently be reduced.

I do not regret buying the Ultramag. I plan to use it for a new 585 ny. But I also plan to pay a bunch to have it polished up nicely. I will probably also change the bolt handle, because the one it has is confusingly similar to my lug wrench.

500,

you could use it for your .600. Why do you want/need a second .585

We just can not get any of this stuff in OZ. It's a real pain in the ass.

Okay, Lads...

I am jealous of you guys, not kidding
PC, just shoot the 585... hell's bell's, you'll be the biggest kid on the block, and can always sell you 585 and upgrade.
BUT....if you have to have it bigger, make it a switch barrel with your 585, so you'll have a decent 'roo stick (600-OK) and a passing grumby slayer... 585...
My friends give me crap about my big stuff.. like "did that 416 actually break the paper and make a hole?" or "that 276 is okay for squirrels, but you'll need to load up for rabbits"... yeah yeah, ... sheesh

But, anyone wanna buy some 585 dies?
jeffe

Jeffesso, but there's somthing Bigger

I think my friend (who also built a .585) and I will be the only ones in our town with .585's I think, and I do feel that it will bring down rabbits if the shot is placed properly

If I build a .600 it will be a seperate rifle, I just have not gelled to the switch barrel thing yet.

pc,

I have a cz550 waiting to be made into the 600 overkill. I want the ultramag for a 585 with 3 down. I plan to fill i the drills in the square bridges and have kind of a double square bridge 585.

500,

my smith got three down on my 602 but he made a completely new mag box and follower, he did them slightly staggered so as the mag box did not look pregnat in the stock.

I would love to get my hands on one of those larger Ultra Mag Action's.

500, what are the Bauska's like ??

I suppose this new .585 is just going to have express sights and 1/4 rib ??

I followed MIkes link to that .585 in anothet thread and came across the Granite arms action, Now I would love to get one of those one day they look great. I imagine there extremely pricey to !!

pc

The new 585 will have an adjustable NECG rear sight and matching ramp front. It is a heavy duty affair, but I am not really interested in filing in a set of sights. Besides, as I vary loads from 650 grains to 1150 grains (cast) and vary pressure from very mild to moderate, I doube that one sight setting could handle it all.

I am not much of a quarter rib guy. A well done quarter rib or integral rib is beautiful, but that's not where I am headed. My new 585 barrel is a pac nor stainless, and the action will be parkerized. The stock will be straight grain english walnut, with a pachmyr decelerator pad. The rifle will be suitable for hunting in the rains of Alaska, and I want to be fully prepared in case one of those grizzlies that got away with a Marlin Guide Gun cast lead bullet in it tries to take it out on me.

pc,

I have not seek a Bauska so I cannot comment.

But I did see a 602 that you might like to hear about. It was carried by a black man in ZIM who has a PH license. But since he cannot speak English he works as a tracker. The 602 came from the factory in 458 win but was rechambered to 458 lott. It only feeds solids as softs hang up, but the tracker uses it for back up so he doesn't care. The stock was split to crap and pinned together in the pistol grip area. The metal retained 10% finish and 80% surface pitting. The wood retained 0% finish. The recoil pad was long gone and the guy just held that walnut up to his shoulder and pulled the trigger. Ouch!

Retail value of such a rifle in the U.S.: $200 to $250.

By the way I had the oppertunity to try that .600Ok case that I made ( since then I seated a bullet in it) in a Sako M75 #5 action. It easily fit into the detachable magazine box with about 1/4" to spare. I was not able to test feed the round as this was a NIB action & the owner was leary of possibly putting any marks (blimishes) on the action. He was kind enough to let me put it into the detachable mag though.

Bear Claw,

Do you think that the detachable box magazine would:

(i) be bent to oblivion by the cartridges banging back and forther under recoil, or

(ii) fall out under recoil?

Also, does it look like the feed ramp is wide enough to accomodate those .620's, after some griding?

??? I Don't know bout dumping or bending the mag but the feed ramp is pretty wide.

[ 08-26-2002, 00:11: Message edited by: Bear Claw ]

500,

lets hope that bear did not steal the hunters Marlin guide gun & begins to shoot back , but you wouldbe safe mate as the bloody thing would jam anyways

I am also going to replace the open sights on my .585 as well 500. I am just not happy with the rem irons. But I agree with you that filing is not an option if you shoot a variety of loads. So this new .585 is not going to have a scope ?? Why is this ?? is the leupold 2.5x on your M70 .585 creating problems ?? I mainly chose a 2.5x compact for mine as you and Rob have them on your .585's and I like the look of them as well.

Also what role will your M70 .585 serve when the new .585 arrives, will you just sight the M70 in for one load and leave it ??. 500 if your building a second .585 then I take it your a fan of this round !!

Back to top, and back on topic. I believe the count is still at 9 for the .600 barrels from Pac-Nor.

PC,

The 2.5 Leupold works just perfectly on my M70 585. The Talley rings hold it with a vise-like grip, and it stays sighted in just fine. No problems at all.

However, when REALLY close to game, a scope is not an advantage any more. So I want an iron sighted 585. I also want the new one to hold 3 in the mag box, while the M70 holds just 2 in the mag plus 1 in the chamber.

I like the 585 nyati round quite well.

But that will not deter me from getting a .620.

500,

what distance do you zero your 2.5x scope at on your .585. ??

I have a 2.5x on my 45/70 and I zeroed that at 70 yards

Anything new? We still need a few more people don't we?

PC

I put my 585 an inch high at 100 yards. That way I still have a chance of hitting something at 150-200 yards. But that's about it.

George,

I believe the count is 9. I was hoping Rob would come back to this thread with an update when he gets a chance (Rob?). It depends on what you mean by needing more poeple. If we can get 12 orders the price will be less, but we will still go ahead with the project if it stays at 9.

Bigbores,

I'm in. I e-mailed Rob just after he left but have not heard back yet. I'm sure he's got a lot of e-mails to respond to. I turned a couple of cases and a few 920 gr bullets (grooved shank with a big flat nose) really impressive round.
My PH is gonna Sh*t when he sees this thing. He already thinks I'm a crazy American, but he'll have no doubt in 2003 when I show up with this.

John

Hey Fritz454 !
Could you please tell me about this thing,what gun ,prize ,loads, bullets (920 gr. bullet,who in the h#&# manufactures those bullets)?
It would have been nice,thank you !

Hi Per577,
The bullets I turned were just something I came up with. I have a CNC shop and once in awhile I have some machine time and I have been turning my own solids when I can. Mostly .416 cal but I have played around with some others. I've got a 353 gr bullet that is the devil himself on elk. I made up a few for 500 grains to try as well as a few in 458 and 474 cal a week ago. He has a sample of the 600OK brass and bullet as well. Maybe he can offer his thoughts on it himself but I think he agrees it is an impressive round.
The action I will be using is a CZ550 mag. IMHO these are the best value for me. They need a bit of work to make them really slick and sound but it doesn’t take too much time and you have a nice mauser type action when you're done.
I'm not sure what you mean by "Prize" and the loads are yet to be determined. I'm looking to duplicate the old 600 NE in a bolt gun. 2000 fps is all I'm looking to get although I think more is possible.
The bullets I made actually weight 911 gr but that was with 360 half hard brass. Once I get the proper alloy the weight will increase to 920 or so gr. I will have to make some minor length adjustments to get the desired weight but this is a very simple thing to adjust.

John