Greetings and Merry Christmas to all.

For a long while work has kept me from building and hunting with a 585 Nyati, but given what Ive read Im thinking a 505 Gibbs may be a better choice. I doubt I have the patience to wait a year or two for a custom- any thoughts on the new 2007 CZ? Looks beautiful, and I read it's glass bed now with two recoil crossbolts.

I had a few of them and they are great guns...the 505 is a Great killer too!If you go custom,try http://www.bijoucreek.com/ or http://www.hunting-rifles.com/ They both make custom and semi custom big bores and I am very happy with there work as they have made several for me! PS.Bijiou can make you a 500 Jeffery in a Win 70 action if you like and American Hunting Rifles uses the CZ to make the 500AHR,the 585AHR and the 600OK (Overkill) if you really need some horsepower!! Tell them Tom sent ya!

NyatiDr:

I have four CZ's two of which are Safari Classics, one in .404 Jeffery and the other in .500 Jeffery. I love them all. The .404 and .500 have been glass bedded and both have had action jobs and two crossbolts. The .500 has a mercury recoil reducer. I know you will get some arguments here but I think they are great. I picked the .500 Jeffery over the .505 Gibbs because I like the cartridge better and I think it works a little better in the CZ but the .505 is a great cartridge as well.

One other thing. My .404 has CZ's wood stock but on my .500 Jeffery, I went with CZ's brown laminated stock for the added strength. I think they have a really attractive laminated stock.

Dave

There is no such thing as a 600 AHR and I REALLY wish you would stop saying it.

It is the 600Overkill, Designed by robgunbuilder.

the 505, which reeks of class, it one of the most inefficient bigbores there is. It takes an odd bullet size, the case is so large you have to fill it would charcoal or 2 ear plugs, and requires things to be right on the edge of design spec. and it BARELY beats the 458lott in power, nominal load

the 500 Jeffe, which you can get in a cz, is a better round.

a 500 a2/510 wells in on a cz416rigby action is easy as falling off a log

and if you want to build a cheap one, try a 500 AR.. take a ruger 77mkII in 7remmag, rebarrel, and have the feeding done.

I'm willing to live with the oddball bore size, since my 505 Gibbs top load with Macifej's 558gr solids will clock over 2500fps. Mind you all, the man did not say common sense big bore.

Rich
DRSS
Knowledge not shared is knowledge lost...

True there is no .600 AHR that cartridge is the .600 Overkill.I have a 585 Nyati and it is a POS.The .600 Ok solved all the problems associated with the NYATI. BTW the 505 Gibbs will never equal a .600 Ok. The Gibbs has its own issues. I should know , I have built all of them.-Rob

Any specs on the .600 Overkill while we are getting it straight?

_ _ _ GR @ ??? FPS ?

900gr upto 2400fps ... it is a belt 600 NE, from 10yards away.. and i hear, at 2000FPs, it is surprisingly low recoil
jeffe

Jeffe,

been checking my 505 Gibbs loading note book, and I must take exception to your definition of the 505 as somehow more difficult to load for. I am not sure how many bullets you need for any given cartridge, but Woodleigh makes soft point and solids, so do our own Macifej and Swageall, and Northfork; and I also have boxes of A2 out in the shop. Cheap practice can be had with my cast bullet loads, and I can load to jacketed power levels at lower pressures.

There are two ways to make 7500+ft lbs of ME, a big case or a lot of pressure. The Gibbs factory loads are in the 45,000Psi range. I have loaded one case sixteen times with a cast load: 650gr GC flat-roundnose at just over 2400fps and the primer pocket is still tight. Extraction is still a one finger bolt lift. I got Macifej's 558gr solids to just over 2500fpt under similiar conditions. How much more power than that can you use?

Rich
DRSS
Knowledge not shared is knowledge lost...

Jeffeosso

I'll bet the recoil is surprisingly low! You've got to be kidding, how much does one weigh?

NyatiDr, you know many of the things said about the 505 were also said of the 416 Rigby but it holds it's own and is the top pick in one of the threads. I love my 505 Gibbs and no matter what the "experts" say you will not regret having one made as I am having an Empire Rifles 505 Gibbs built. I've shot one quite a bit and if you talk to those who have ACTUALLY USED ONE, they will all tell you go for it, not the least of which is Kevin "Doctari" Robertson. Remember you can shoot 525's and 600 grain bullets something that few cartridges have the versiltiy of being capable of doing, to me that's the best of both worlds. Like the 416 Rigby it can be out done, on paper, by other cartridges but in REALITY...it just plain WORKS!

quote:

Originally posted by jeffeosso:

the 500 Jeffe, which you can get in a cz, is a better round.

Jeff, I agree. I have a friend who has some 570 grain bullets for me but I only have load data for the 535 grain bullets. If you have some data for the 570 grain bullets, PM me, okay?

Dave

quote:

Originally posted by Robgunbuilder:
True there is no .600 AHR that cartridge is the .600 Overkill.I have a 585 Nyati and it is a POS.The .600 Ok solved all the problems associated with the NYATI. BTW the 505 Gibbs will never equal a .600 Ok. The Gibbs has its own issues. I should know , I have built all of them.-Rob

Rob,Sorry about that! I should know,I had them build me two of them!

Hey NyatiDr!

Get the 505! Ignore all these guys who are blubbering about this & that! The 505 is inefficient BS.....The 600 is the best (overkill is right). Bottom line here is that you can buy a nice 505 off the rack, you can buy brass and bullets and dies anywhere. I'll even send you some bullets to try if you like.

quote:

There are two ways to make 7500+ft lbs of ME, a big case or a lot of pressure.

I get your point IS, but I don't think the 500 A2 is that bad, pressure-wise. The A-Square manual says the 600gr soft at 2467 fps (which rocks your socks) using 118gr of RL15, only generates 57,500 PSI. I guess it depends on your perspective, but I don't consider that "a lot" relative to other modern cart's.

Cheers,
Canuck

Rich,
I know you are a gibbs fan, and I am a 500 jeffe man ... and bias certainly comes into play in bigbores. The man asked for opinions on the gibbs, and I gave him mine .. in fac,t let me finish answering his question.l get the 500 jeffe!! LOL .. take this as if we are having a coffee and dicussing it, rather than how it could be read as exchanging broadsides (lol)
Yes, the gibbs is a great round, but for comparison sake, a GIBBS is a 525gr bullet at 2350, not a 600 gr load or a 525 at 2500, those are greater tham cip/saami/nominal loads. You can load a 470NE to 2500fps (actually seen it done in a heym) as it is the same case capacity as a 470mbogo ... but one doesn't do that in a double FOR LONG, and exceeding design specs scares me
Yes, you can jack a 505 up, but you are SERIOUSLY working on bolt thrust. There's basically two commerical bullet makers for the 505, and northfork DOES NOT make a 505 bullet, mac and swageall are entirely niche, and not available to everyone.

Its not a question of power, but practicality.. its a PITA to get PLINKING jacketed bullets for, and the cases are (just like the 500 jeff) crazy prices. Remember, I did a group buy on a couple thousand cases of both...

At FACTORY loadings, the gibbs requires an inefficient powder, or a filler, PERIOD. in fact, the case is too big for all practical purposes. The jeffe/schuler was designed to be a better case for the superior german powders, then AA and Fred came up with the 50xwebby case, which performed the same with less powder, and then the 500 AR does the same exact thing. It matchs the FACTORY loading of the gibbs/jeffe fraturnal twins, with nearly 40gr less powder, in a standard length and sized action.

i just can't warm up to the gibbs, no matter how long i have tried... its a great round, no doubt, just not for me... i would have a free one just long enough take a couple heads of game and then to sell it. so, to save myself frustration, i haven't bought one.

oh, Rich, in sporting rifles, the only way to get 7500ft/lbs is BOTH huge case and high pressure .. the 550 magnum gets 8000 at 65,000 ... and 7500 at about 60k, based off lab tested results.. the gibbs case, using a longer bullet and less cross sectional (alot less), is going to be right there with it in pressure.. that famed 25% of gain formula works up AND down.. just can't get away from it much .. the gibbs is roughly 17% larger case than the 550 magnum, and the .550 is roughly 9% larger than the .505 .. net, 8% total gain, divided by 4, is about 2%,comparing the 505 gibbs vs the 550 magnum... 2% aint much... about the same difference NET between the 375 HH and 375 ruger ....

Oh, yeah, the fella can also order a 550 magnum from cz custom shop, and have the best of all worlds... super high SD, execellent velocity, cheap cases, and 3 commerical bullets (Hawk, Barnes, Alaska Bullet works) and Swagealls and a couple other boutique bullet makers.

quote:

Originally posted by jeffeosso:

At FACTORY loadings, the gibbs requires an inefficient powder, or a filler, PERIOD. in fact, the case is too big for all practical purposes. The jeffe/schuler was designed to be a better case for the superior german powders, then AA and Fred came up with the 50xwebby case, which performed the same with less powder, and then the 500 AR does the same exact thing. It matchs the FACTORY loading of the gibbs/jeffe fraturnal twins, with nearly 40gr less powder, in a standard length and sized action.

i just can't warm up to the gibbs, no matter how long i have tried... its a great round, no doubt, just not for me... i would have a free one just long enough take a couple heads of game and then to sell it. so, to save myself frustration, i haven't bought one.

I am not bashing anyone with a .505 Gibbs but I think that Jeff is exactly correct. In a bolt gun, at factory specs, IMHO the .500 Jeffery is a much better cartridge.

I am convinced that like the .450 No. 2, most guys are attracted to the .505 simply because of its' sheer size but it is the size of the cartridge that makes it unsuitable for all but the largest and bulkiest of actions. The Jeffery just works better in a bolt gun.

Dave

If you're only going to own one big bore in your entire life, then which one you choose may matter. But it sounds like your interest is broader so go for the one you can get fastest/cheapest for now and work on the next "ideal" one while you're having fun with the current gun. If it will be a CZ first, then the 505 makes sense as would the 550.

All good points Jeffe, but not all germane to the discussion and choice. I PM'ed several folks here that reside/guide in Africa and their answers were 100% in favor of (more likely)finding 505 Gibbs VS 500J ammunition in the specialty shops there.

As far as finding bullets, I think everybody knows who Woodleigh is and how to find those bullets. Anyone who posts here asking where to find 505 bullets will get a reply from Macifej and Swageall within hours.

500J = 160gr H20 capacity
505G = 180gr H20 capacity.
Can't get around those numbers. It must be important, look at all the hoopla over the 375R with a 6% capacity increase over the H&H...

Cast bullets are available for either, and brass is plentiful.

EEE-ther, EYE-ther, Po-tay-to, Poe-tah-toh.
The Gibbs case just has the size, and if you are buying a CZ the rifles have the same dimensions...it's a wash.

Rich
DRSS
Knowledge not shared is knowledge lost...

There ya go again Rich! Applying logic to an opinion thread.

Obviously a modern 505" isn't your grandfather's Oldsmobile. The brass is better, the powders are better, the bullets are better, and of course the rifles are better too.

Ain't no replacement for displacement!!

Thanks for the replies, Ill look into the cz 550 safari mag in 505 Gibbs

quote:

Originally posted by Idaho Sharpshooter:
All good points Jeffe, but not all germane to the discussion and choice. I PM'ed several folks here that reside/guide in Africa and their answers were 100% in favor of (more likely)finding 505 Gibbs VS 500J ammunition in the specialty shops there.

As far as finding bullets, I think everybody knows who Woodleigh is and how to find those bullets. Anyone who posts here asking where to find 505 bullets will get a reply from Macifej and Swageall within hours.

500J = 160gr H20 capacity
505G = 180gr H20 capacity.
Can't get around those numbers. It must be important, look at all the hoopla over the 375R with a 6% capacity increase over the H&H...

Cast bullets are available for either, and brass is plentiful.

EEE-ther, EYE-ther, Po-tay-to, Poe-tah-toh.
The Gibbs case just has the size, and if you are buying a CZ the rifles have the same dimensions...it's a wash.

Rich
DRSS
Knowledge not shared is knowledge lost...

Rich, your hearing but your not listening. It's the size of the Gibbs case that IS THE PROBLEM and if you buying a CZ .505, your buying a push feed gun.

Dave

yes, I own a CZ 550 American Safari 458 Lott. It has a lamanated Stock. Seems to want to put all rounds into one inlarged hole. CZ all the way

I prefer the .500 A-Square - i.e., the .510 Weatherby Magnum.

It's got a big enough case to get 2,500 fps with 570-600 grain bullets. The brass is not too expensive and is readily available. And there are plenty of big .510" bullets on the market, too.

Nothing against the Gibbs - it's a fine round, and with ammunition and rifles now available at retail, it's looking better all the time.

Look guys, I own,have built and regularly shoot nearly all known Big Bores including the 505 gibbs, .500 AHR,.500a2, 585 NYATI and.600 OK 1&2 . Frankly the 505 Gibbs is my least favorite although the gun I built for it is probably the best I've ever done. Why? Bullets are expensive and the cases have a nasty tendency to push the shoulder back. Power wise, its no better than the .500a2 and a heck of a lot more expensive to load for. I can't shoot military .50BMG pulls out of it like I can my .500 a2 and I cry each time a case splits. Its not an easy cartridge to get to feed reliably and other than the nostalgia factor, it would be as dead as the dodo. THERE Just isn't anything the 505 Gibbs can do that you can't do with other cartridges. If your looking for more power you need more case capacity or you try and run stupid pressures ( .408 CHEY TAC CONCEPT). The only thing going for the Gibbs is the CZ550( once you put a grand into getting it to feed reliably). Thats not a bad deal.-Rob

Dave Bush,
I cannot understand why the CZ .505 Gibbs is a "push feed."

Ditto MR and Rob.
I have a couple of 500 A2's for serious shooting, and a CZ .505, just for kicks.
The 500 Mbogo in the works (due any day now!) is to correct the nonproblematic micro-rebated-belted 500 A2 case. It is purely a wildcatting delight sort of thing, a .510/470 Mbogo 3" Rimless Express.

A 500A2 with 600-grainer at 2500 fps will hit harder on target and softer on shooter, shoulder and wallet, than the same ballistics in a .505 Gibbs.

Ditto the 500 Mbogo. No chamber thrust worries on the action either.

Anyone who is stuck with using a .505 Gibbs could not do any better than the 558-grain S&H FN brass solid at about 2300 fps. No worries for the rifle there.

Since the 500A2

If we all followed Rob's logic to the extreme we'd be best off buying 460 Wby's from the custom shop for $3,500. The Norma brass is cheap and the best there is for mass produced. Cheap bullets, cheap everything and if you learn to use it well nothing is better at any price. You can shoot a 300 Grain spitzer and a 600 Grain whatever out of the same blaster. If you need more capacity than 2+1 add a drop box.

Pushfed and no milsurps, and not quite enough kick in a 460 wby to fully satisfy. Too common to be interesting to the jaded.

You need to follow my logic more carefully than that. The CZ550 is the perfect gun to convert to a 500 a2. Take your 505 Gibbs replace the barrel, chamber, add decent sights and get the feeding right in 5 minutes with a file. There is no simplier conversion. I've done 5 of them. All were a snap. Converting a Weatherby would be easy,but you'd still have a Weatherby. Oh yes there are lots of 460 weatherbys available at gun shows still with their original boxes of ammo for sale cheap. .50 BMG Mil surp pulls are fun but you can also single load A-Maxs if you need more accuracy.
The .500a2 will do anything a .505 Gibbs will do and more. Its without a doubt the best bang for the buck there is. Try it you'll become a believer!-Rob

the 500 A2 is dead as the dodo, just like it's brother the 585 T-Rex.

This conversation amazes me, but I keep trying to see the logic in the negative comments...

You can go to Cabela's in the morning and buy 505 Gibbs rifles and ammunition. You cannot find ANY 500J or 500A2 or 510 Wells Express rifles or ammunition. I know, I just ran those thru their nationwide finder and came up zero. Jamison, Norma, and Bertram are three mainline brass manufacturers who offer 505 Gibbs brass. Red Willow, whatever their name is now, offers brass, I have some. Woodleigh, A2 (if they are in business this week) offer bullets. Macifej and Swageall also offer them here for the asking. I would expect they are also available from Norma, and others that I am not aware of...

As far as all four or five of you talking up the options mentioned, Newton and the H.P. White Laboratories have proved this simple statement: there are only two ways to make ME, a big case, or high operating pressures.

1. .50's on the 460Wbee case..........144-148gr capacity
2. .50's on the Jeffery case..........160gr capacity
3. .505 Gibbs case....................180gr capacity

At the same pressure, the bigger case produces higher velocity...period. There is no arguing this, unless you are also a card-carrying member of the Flat Earth Society. At the same velocity the bigger case produces less pressure. This is also fact, not subject to interpretation; unless you also believe those Reality TV shows and Professional Wrestling ARE reality-based.
To increase ME you have to have a bigger case, or be willing to play around with higher pressures.
That's it!! There are no "...if's and's, or but's...". Deal with it as best you can, but there is no way around it.

Make a note, wishing does not make it so. Calling any cartridge that is loaded by ammunition factories oddball is akin to peeing your pants wearing black Wranglers: it gives you a nice sort-of warm feeling but nobody else really takes notice.

NYATIDR: be happy, buy a 505 Gibbs, and know if you need ammunition in Africa you will be able to buy it, unlike any of the second-rate unhappy options listed here.

Rich
DRSS
Knowledge not shared is knowledge lost...

You need three bullets for a DGR, a soft point, a solid, preferably the same weight and bearing surface, and an equivalent weight cast bullet. Two for killing dangerous game, the third for 20-30 or more rounds a week of practice.

Well Done Sir Rich!!!



Horneber also makes .505" brass which is in stock at Huntington's.

Pressure is being used to confuse and distract here, it is not an issue at all in the 500A2. It could be an issue in the .505 Gibbs: bolt thrust.

If you get a .505 Gibbs up to 500A2 performance levels, you are on the ragged edge of bolt thrust.

The ragged edge never comes with the 500A2, because you would have to get into the 75Kpsi levels to reach the levels of bolt thrust given by the .505 Gibbs at 55Kpsi.

Besides bolt thrust, that huge Gibbs head size is also a nuisance in causing skeletonization and weakening of the bolt face to accommodate it.

Medium powders like RL-15 fit perfectly in the near 150 grain H20 capacity of the 500A2 with 570 to 600-grain bullets at 2400 to 2500 fps and pressures of 50K to 60K: far less than needed to stress the action or disintegrate the brass or cause any problems whatsoever in a bolt action with Rigby head size.

You have to use a filler with the Gibbs or use much larger charges of slower powders and pay for it. Another nuisance.

How many original .505 Gibbs did they make? 23 of them?

It is quite the fad with the inexpensive CZ since 2005.

Working 500A2's must outnumber the .505 Gibbs by at least 1000 to one in the real world (hyperbole thrown in to match the usual tone of rhetoric displayed by some posters here).

RIP!

True stuff but bolt thrust isn't an issue in most modern rifles....even a cheap-o (gasp) like the CZ. Hoop/radial stress would be a bigger concern in action/barrel combinations of unknown material state (read most all new and old). How many original Gibbs were built? Who knows but it doesn't matter because we are talking about real guns not antiques. Lots of shops build new Gibbs on new actions so who knows how many there are out there. One thing for sure is that the 500 A2 is a dead duck designed by a dead duck company and does nothing appreciably better than the 460 which spawned the pig.

The only reason the Gibbs isn't huge commercially is that there are no high quality actions mass produced with the slightly larger proportions needed! (I might be able to solve that problem too! )

.........Mac,, Mike LaGrange thot and proved the 500 A-Sq. did alot that the 460 didn,t .....The 500 A-Sq. is not a dead cartridge and you wouldn,t want to use it duck hunting !!! ...John Buhmiller didn,t think the 505 killed any better than the 450 Ackley did .....

RIP:

The only actions that are really big enough for the .505 is the Granite Mountain action with the .75-inch bolt and perhaps the Heym action. On the CZ, you have to cut away the rim around the bolt face to almost nothing. It is essentially a "push feed."

My good friend just ordered a Gibbs from Empire Rifles. They are building it on a Granite Mountain action rather than their own action. They tried very hard to talk him into their new .505 Empire cartridge which I understand to be simply Weatherby magnum brass with a straight taper to .505 caliber and an overall length of 3.6 and which does not require a .75 diameter bolt. Frankly, if you want a .505. I think that is the way to go.

Some people see the rebated rim on the .500 Jeffery as a problem. The designers saw it as the solution to all these problems.

Dave

NyatiDr….

Here is my experience with the CZ in 505 Gibbs…

I bought one from Cabela’s about a year and a half ago ($2,250)……

Yes it was a good looking rifle, but it did have some feeding and ejection problems which I’ve come to expect from most “out of the box†CZ’s (between me & my shooting buddy we’ve owned at least 10 -- 15 and all needed work) ….

So I’d plan a trip to the smith when purchasing any OTC CZ to get it 100%...

With that being said if you were already looking at the Nyati why not just take the plunge and go for the 600 Overkill….

That’s exactly what I did…

I figured that by the time I had my 505 straightened out I’d have at least $3,500 in it, for not much more $$$ you could have AHR build you a rifle chambered in 600 OK on a CZ action….

Perhaps the 2007 CZs in 505 are factory ready but I doubt it….and the 505 is a serious step down in power from the 600 Overkill….

If you want a 505 for whatever reason then go for it, but I figure you’d still be in for a wait either way…

Just my two cents

STAY ON TASK!!! He didn't ask about other cartridges. I got a yankee dollar or two that says there are more commercial 505's sold than the rest combined. He is not interested at this point in investing two years and ten grand in a rifle, he wants to drive over to Cabela's and fork over about a fourth of that; and take a 505 Gibbs and ammunition home.

Rich
DRSS
Knowledge not shared is knowledge lost...

I'm sorry, but the 505 Gibbs would be totally worthless and historically obsolete if it wasn't for the CZ550 and both of the ones I have would not feed reliably at all out of the box. BTW next to the .500 Jeff its the next worst feeding cartridge in existance! One of my factory CZ's also cracked its stock within the first 20 rds! So much for just run out and buy one and become the big Bwana! Frankly,the were both organ donor guns for .600OK's The CZ can handle very high bolt thrust levels as we all know and hoop strength is not an issue at the power levels we are talking about here. Remember, I proofed the .600 OK on a CZ550 at 85Kpsi ( approximate) and it didn't set the lugs back or show any other destructive signs! The issue is the .505 cartridge. Lets face it the .505 is an odd ball diameter( the only thing in .505 is the Gibbs) and very few people want to get involved with that. The .577 has much more appeal for just that reason! The .505 Gibbs case is expensive ( because there is not much demand for it),has too much volume for the diameter and is a PIA to work with. I think all .505 Gibbs cases should be converted to .577 as that at least makes sense. Too bad it requires fireforming!
The .500 a2 is simple. Run a .510 expander through a .460 WBY case and out pops a fully shootable .500a2. Belts are cool that way! I load full power and keep the happily fireformed cases. They last forever! Oh the .500a2 isn't dead, its very very very much alive and a way better round than the Gibbs. Bullet selection is terrific, performance is spectacular and nothing is easier to gunsmith.
When I built my .505 Gibbs, I really stressed over whether I should just make the .510 wildcat of the Gibbs or stick with the .505. In the end, I deceided to keep the .505 Diameter and now wish I had not.
Being able to shoot a wide variety of bullets is a very attractive option the Gibbs simply doesn't have. Being able to shoot .50BMG pulls is just plain cool too!-Rob

quote:

The .577 has much more appeal for just that reason! The .505 Gibbs case is expensive ( because there is not much demand for it),has too much volume for the diameter and is a PIA to work with. I think all .505 Gibbs cases should be converted to .577 as that at least makes sense.

Did the good doctor (scientist) just say all 505 cases should be turned into 577's