leaving why anyone would want to as a question for another day, structurally/component wise is their any problem running a 505 full tilt in the CZ? By full tilt I mean making use of the full 179 grain capacity at max pressures, which should be over 9500ftlbs.

No problem -Rob

That settles that. Thanks Rob

505 Gibbs loaded to 9500fp. of energy = 600gr/2670fps.

According to Powley it will have 5320 BAR or 76000psi. Sad, considering that the CZ has 3800 BAR limit stamped on the receiver.

Pyzda

Not concerned with load software estimates for big cases, they are usually shit.

Would the brass be able to take those pressures?

I wouldn't be aiming to get anywhere near the number above, as I don't think it would be necessary. As to regular 60k territory I would think current Norma/Horneber would be up to the task of handling similar pressures to other centrefire brass.

quote:

Originally posted by Karl:
I wouldn't be aiming to get anywhere near the number above, as I don't think it would be necessary.

+ 1

If you wanted to do it, I would ask why the need and what does it achieve ?

I ran some examples through quickload just for interest, and it looks quite feasible to get 2670 fps with the 600gn Woodleigh (the only bullet I tried) using either Reloader 22, Norma MRP, or VV N560. All these achieved 2670fps for the 600gn bullet with under 65,000 psi. As they are all fairly slow there is some powder compression, between 8% and 12% depending on the powder. Of course this is all theoretical, and may not be possible in every rifle, but it does give some indication of the potential power of this cartridge.

Whether one would want to do that is another thing entirely. My tolerance runs out at 600gn at 2380, which is still a mild load in my rifle (pressure wise), but very un mild in terms of recoil. At that point I chose not to test any further.

I suppose with a muzzle break and a recoil reducer, it would be another story, but there is more than enough power for anything with my standard load of 600gn at 2270 fps, so I am not motivated to try for more.

I was just going to ask why??? Holy crap anyting above 2250 with a 600 grain bullet in my gibbs is teeth shattering...Enjoy pushing those to 2500fps...

Ed

No practical reason to do it and have to admit it does defile the pedigree of the 505gibbs a bit to tamper with its historical loads.
Main reason is personally just interested in fast bigbores. A hot 505 is like a bigger 460 wby, actually it could probably shoot as ffast as the 416 wby according to the estimates. I'm not looking to blow any actions up trying though- 525-600 grain loads that shoot as flat as the 375H&H with 270-300grainers would be the goal. I think the gibbs would do this without breaking a sweat.Coming down from 585 class guns the recoil doesn't scare me too greatly. Well maybe just a little

quote:

Originally posted by PD999:
Would the brass be able to take those pressures?

Bertram will not. They are soft and will stick every time. Bell/Jamison and maybe Norma will. I know because I just had to find out. Most people who shot mine with that load will tell you once is enough from a 10 lb rifle with no muzzle brake. Its the recoil velocity that kills you, not necessarily the total pounds feet of muzzle energy.

tigger yes regular bertram would not get close. But I wonder is his latest stuff any better. He is now making bulk chey tac brass with the strenghtened web and all that jive for the ultra long range crew who run things at crazy pressures. being its the same basic case essentially wondered if his gibbs brass might have improved in the process...

I have shot tiggertate's 505 at full tilt boogy. 600@2600fps, it is a STUNT LOAD ONLY. I would never hunt any DG with it. A timely second shoot is not possible. I agree with Harry!

Keith

my working load is 535 barnes FNS. 141 grs of rl 22. it is stout and has shot through 30 pieces of 1 1/8" hard plywood pads for heavy eq. That is 34" inches of hard wood. I have loaded up to a listed max of 151 grs. No problem with any bolt lift or ejuction, primers are flat though. The recoil is rough, it goes from being a hard push with a big boom, too a realy hard fast punch with a sharp crack. I think the second load gets in the proper pressure curve for the powder. 5 of those off hand is about all I want.I shot 3 offhand at clay targets at 200 yards. It resulted in two hits and the 3rd shot being close enough that it was broken by the massieve amount of mudd blowing out of the wet berm. Cantolope size holes. I broke my shot about 2" over the top of the target. Thats about the same as I would hold over for my 308 with a 100 yard zero. The 151 gr load slowes down the second shot due to excess recoil. it is like takeing a good right cross. the action is the montana ph,brass by jammerson.

JD

quote:

Originally posted by Karl:
tigger yes regular bertram would not get close. But I wonder is his latest stuff any better. He is now making bulk chey tac brass with the strenghtened web and all that jive for the ultra long range crew who run things at crazy pressures. being its the same basic case essentially wondered if his gibbs brass might have improved in the process...

If he's using the same alloy and internal dimensions in both, it should work.

338

Is it under 60000 PSI or a 60000 CUP ?

In the Powley it comes as 59900 CUP. and 76000PSI, but again the default powders here are IMR 4350 and 4831.

It's obvious that the slower powders would have less pressure, but how much less?

The manufacturers common test proof loads are usually around 30% above maximum loads.

That means that if the Powley figures are correct it would be shooting a test blue pill every time.

Pyzda

Bell Brass seems to handle pressure well.

It was used for the 505/530 at full loads
and no problems.

Karl, sounds like you are thinking of a 375/505 setup. I have two like that and I use Jamison cases. Load upto 141 gr retumbo and get 3270 fps with 350gr smk. Recoil no problem with muzzle brake. Groups 9" at one mile but my smith got 4" three shot group with it. Shot a elk at 636 yds and exit wounds 5" despite it not being a game round. For my regular Gibbs 505 I use 144gr R-25.

quote:

Originally posted by LR3:
Karl, sounds like you are thinking of a 375/505 setup. I have two like that and I use Jamison cases. Load upto 141 gr retumbo and get 3270 fps with 350gr smk. Recoil no problem with muzzle brake. Groups 9" at one mile but my smith got 4" three shot group with it. Shot a elk at 636 yds and exit wounds 5" despite it not being a game round. For my regular Gibbs 505 I use 144gr R-25.

I an working on a 416/505. I will glass bed the stock this comeing week. I am hoping for 2900 fps with a 450 gr hornady match.

JD

quote:

Originally posted by J D:

quote:

Originally posted by LR3:
Karl, sounds like you are thinking of a 375/505 setup. I have two like that and I use Jamison cases. Load upto 141 gr retumbo and get 3270 fps with 350gr smk. Recoil no problem with muzzle brake. Groups 9" at one mile but my smith got 4" three shot group with it. Shot a elk at 636 yds and exit wounds 5" despite it not being a game round. For my regular Gibbs 505 I use 144gr R-25.

I an working on a 416/505. I will glass bed the stock this comeing week. I am hoping for 2900 fps with a 450 gr hornady match.

JD

Interesting thread.

And common sense. Why else would one design a case with a 150+ grain appetite, if not to feed it?

PS: That 450 grainer ought to handle 8500 ft lbs, but a .416" muzzle is a little tight for such a capacity, so approach through appropriate build ups.

Anyway, it was exactly the considerations on this thread that lead me in two different directions.

a. For .416"s a Rigby capacity needs to utilize 6000-6200ft lb. loads. Otherwise one can just get a 416 Rem/Ruger. Loads of 350 grain bullets at 2800-2850 fps make a great walk-in-the-forest rifle. The cartridge feels good in the hand and comes pretty close to being an ideal all-Africa round.

b. So at .510" calibre (including .505"), one should choose the cartridge/case capacity by the level of power that one wants to carry and shoot. I decided on 7000 ftlbs (6500-7200), so I realized that the Gibbs, Jeffrey, and even the A2/Mbogo were just burning extra powder. The 500 Accurate Reloading handled everything that I wanted. Cartridges are compromises that require multi-faceted, personal decisions. Enjoy your shooting.

quote:

Originally posted by Pyzda:
338

Is it under 60000 PSI or a 60000 CUP ?

In the Powley it comes as 59900 CUP. and 76000PSI, but again the default powders here are IMR 4350 and 4831.

It's obvious that the slower powders would have less pressure, but how much less?

The manufacturers common test proof loads are usually around 30% above maximum loads.

That means that if the Powley figures are correct it would be shooting a test blue pill every time.

Pyzda

It is under 65,000 PSI, according to quickload. It is theoretical but reasonably close in many cases. However I have seen some big differences from Quickload predicitions. If you do the work to measure bore, chamber, case and bullet dimensions, and powder characteristics you can get very close results, but there are many variables, so I only take it as an indication of what can be achieved.
Some powders go well over 70,000 psi to achieve that velocity, and all those that did achieve the highest velocity for < 65,000 PSI needed slow enough powders that there was some compression. Norma MRP (not MRP2) was the best at 61,844 PSI, for 2671 fps.

Actually it is quite interesting. I was recently involved in some reloading work to find powder charges that duplicate original 525gn factory ballistics of 2300fps. We tried AR2213SC, AR2217, ( H4831SC, and H1000 respectively) Vhitavuori N160, Win 780, Reloader 19, 22 and 25, and got reasonable loads with each. The two things noticed were AR2217 and Reloader 25 kick much more noticably than any other powder, and Win 780 has a very different muzzle report than any of the other powders. A very distinctly different BOOM! The two rifles we had (mine based on a GMA action, and a freinds based on M17 Enfield, sometimes also called a P14 Enfield) exhibited significantly different velocities too, up to 150 fps difference for the same loads, so it only goes to reinforce the general rule that every rifle is different, and don't just use other people's loads without carefully working them up in your own rifle.

My standard powder for factory ballistics is Reloader 15. It has the least felt recoil of any of the suitable powders for those velocities. The slower powders have better loading densities but there is a price.

If you want to step up a little, I still have my 550 Gibbs reamers; and Hornady makes dies.

Ask the gentlemen who shot it at Hoot-N-Shoot I about five years ago in Houston.

quote:

Originally posted by 416Tanzan:

quote:

Originally posted by J D:

quote:

Originally posted by LR3:
Karl, sounds like you are thinking of a 375/505 setup. I have two like that and I use Jamison cases. Load upto 141 gr retumbo and get 3270 fps with 350gr smk. Recoil no problem with muzzle brake. Groups 9" at one mile but my smith got 4" three shot group with it. Shot a elk at 636 yds and exit wounds 5" despite it not being a game round. For my regular Gibbs 505 I use 144gr R-25.

I an working on a 416/505. I will glass bed the stock this comeing week. I am hoping for 2900 fps with a 450 gr hornady match.

JD

Interesting thread.

And common sense. Why else would one design a case with a 150+ grain appetite, if not to feed it?

PS: That 450 grainer ought to handle 8500 ft lbs, but a .416" muzzle is a little tight for such a capacity, so approach through appropriate build ups.

Anyway, it was exactly the considerations on this thread that lead me in two different directions.

a. For .416"s a Rigby capacity needs to utilize 6000-6200ft lb. loads. Otherwise one can just get a 416 Rem/Ruger. Loads of 350 grain bullets at 2800-2850 fps make a great walk-in-the-forest rifle. The cartridge feels good in the hand and comes pretty close to being an ideal all-Africa round.

b. So at .510" calibre (including .505"), one should choose the cartridge/case capacity by the level of power that one wants to carry and shoot. I decided on 7000 ftlbs (6500-7200), so I realized that the Gibbs, Jeffrey, and even the A2/Mbogo were just burning extra powder. The 500 Accurate Reloading handled everything that I wanted. Cartridges are compromises that require multi-faceted, personal decisions. Enjoy your shooting.

Tanz:

You da man!

Everything loaded to the max. Remember, that old .416 Rigby built it's reputation with a 410 bullet at 2300 fps out of a 26 inch barrel.

Good hunting my friend!

quote:

Dave posted:

You da man!

Everything loaded to the max. Remember, that old .416 Rigby built it's reputation at 2300 fps out of a 26 inch barrel.

Good hunting my friend!


Dave

Dave, I thought that the 416 Rigby was rated for 2400fps.
But either way, if I were going to take a rifle with 400 grain bullets at 2400 fps into the forest, I would get a 416 RUGER. That produces what it does at 60k PSI, which is a very reasonable, modern load. Why would someone want to burn 20 more grains of powder to do the same thing in a longer action and heavier rifle?

Now "max" is a relative thing. If I had a 500 Jeffrey, I would test loads from 7000 ftlbs up to 8500 ftlbs and look for the most accurate node. The highest accurate node would be my 'max'. Isn't that what we do with any rifle? The reason for a 300 WM is to outperform a 30-06, but the max in any rifle depends on what he handles most accurately.

Tanz:

If you want some tough guy load data for a 500 Jeffery, check these out:

http://www.realguns.com/loads/500jeffery.htm

Personally, I just load 110 grains of Reloder 15 with a 535 grain Woodleigh PP or Barnes Banded Solid. That preety much duplicates the old Kynoch load of 2400 fps with a 535 grain bullet out of a 28 inch barrel. My gun has a 24 inch barrel. I never saw any reason to go to a 570 grain bullet or load it faster. Modest recoil and enough punch to kill a dinosaur.

Thanks Dave. Joe (RealGuns) has a nice article on letting a Jeffrey do its stuff.
http://www.realguns.com/archives/156.htm
http://www.realguns.com/archives/157.htm

Please note: I am happy with a 7000 ftlb. limit. That is why I built a 500 AccRel.

I think Jeff's 500 AccRel is a better design than my Jeffery. If I had it all to do over again, I would just build the a 500 AccRel.

Given good bullets, faster is better. 2,500 fps is just about perfect.

Does anybody really think CZ would chamber the 505 Gibbs in their action and it could not take full power loads? Not Likely!
Remember, I blue-Pilled 2 different CZ550 actions during the development of the 600Ok at 85KPSI twice and compared all dimensions before and after. My conclusion was perfectly safe. Top load in the .600OK in a CZ550 with 900 gr bullets was 2400fps at 65KPSI. .600OK Number 1 has digested about 50 rnds at that level and is still going strong after over 1K of the 2200fps loads. These are quite strong actions. You have nothing to worry about.-Rob

There is no doubt, that the CZ will take full power loads in .505 Gibbs .

The question here is, how many shots it will take before something will give up.

Is it 500, 1000, 2000, 10000? Who knows, but a stress line repeative accumulation is a very serious problem and it happens to anything.

What is the most worrying is, that a catastrophic failure will happen from repeative stress where the force is far bellow the Yield stress.

Lets say racing engines crankshaft/conrod is not going to break after 5 miles of racing,

but there will not be a single engine that will have a crankshaft/conrod left in one piece after 1000 miles of racing.

Pyzda

quote:

Originally posted by Pyzda:
There is no doubt, that the CZ will take full power loads in .505 Gibbs .

The question here is, how many shots it will take before something will give up.

Is it 500, 1000, 2000, 10000? Who knows, but a stress line repeative accumulation is a very serious problem and it happens to anything.

What is the most worrying is, that a catastrophic failure will happen from repeative stress where the force is far bellow the Yield stress.

Lets say racing engines crankshaft/conrod is not going to break after 5 miles of racing,

but there will not be a single engine that will have a crankshaft/conrod left in one piece after 1000 miles of racing.

Pyzda

With the 505 Gibbs at full power, you are talking about 153 grains of powder, 600gn bullet at 2670 fps. The recoil energy is 147 ft lbs in an 11 lb rifle, and the recoil velocity is 29.3 fps. I think that in most cases the shooter will give up long before they hit 500 rounds, unless you add muzzle break and recoil reducers, or unless they are just much tougher than me!!

Rich your 550 would be good but have me back in 585 class again Am still trying to talk myself out of putting a .530 barrel I have on a CZ 416. LR3 the cheytac/gibbs wildcats are interesting but I am too lazy for all the technical side of ultra long range, you guys are walking ballistics computers.

Tanzan sounds like we have the same tastes. I like the fact the gibbs can push bullets of a certain SD faster than almost all bigbores, only the 416wby and select ultra long range wildcats can beat it. It even keeps pace with the 300 H&H. Not bad for a distinguished 100 year old gentleman.

338 thanks for your PSI estamites, don't get too tied up with Pyzda, he is 'a lot like' one of our old trolls ToddE axel in particular hates 500's at high power and lots of powely waffle about them. I don't mind him on threads as he stimulates discussion as long as he keeps control of himself.

In response to your arguments Pyzda on failure at 1000,2000, 5000 etc it could happen to any gun. It could happen any time you exceed a powder manufactures maximum printed load(which we all do) could happen any time we wildcat an action- which manufacturers refuse to endorse, or gunsmith an action- which voids warranty. In other words all this and running CZ's hot, falls under time proven common sense as to whether it can be done.Try to exercise some yourself.

quote:

Originally posted by Karl:
...

Tanzan sounds like we have the same tastes. I like the fact the gibbs can push bullets of a certain SD faster than almost all bigbores, only the 416wby and select ultra long range wildcats can beat it. It even keeps pace with the 300 H&H. Not bad for a distinguished 100 year old gentleman.

I'm not sure what units you are using for the following, but relative levels are easy to figure:

quote:

Tanzan the figure I like most about the 505 and only being a weatherby type nut is '47500' which is a max load KE divided by cross sectional area. Rough guide for how flatshooting the cartridge potential is. Obviously short fat bullets slow down the big bores a lot but at the start the gibbs is as fast as a 416 wby or 300H&H . In 30 cal only a 300win mag or faster will have the edge on it wiuth 50000 or more- in bigbores nothing over 378 beats it apart from overbore/ultra long range wildcats. Not bad for a big fat 100 year old heavyweight gentleman!

The .510" bores are almost exactly 150% of the area of the .416". The .505 will be 147% greater in area. That means that a 505 will need 1.47x6200ftlbs to equal the flatness factor of the .416. 1.47x6200 is 9114ftlbs. I've never hunted or shot something at that power level, but it would seem a lot to pay in order to have an 'all-around' rifle. I can just imagine hunkering down on that 201 yard oribi shot last October. The Rigby was delightful, even on top of bruises from a lot of sighting-in the day before. I'm just not sure what a full-power Gibbs would feel like in a normal walk-about rifle (no muzzle break, no recoil absorbing stock, under 11 lbs. fully loaded and scoped). Like I said above, one must make compromises and I've chosen a 7000 ftlb ceiling for a 50-cal walk-about rifle. That means that it is a great buffalo and under-300 yard rifle, but the 416 Rigby gets my nod for all-around Flat and Powerful .

For comparison, and using your flatness factor formula, a 338 would need to be loaded to 4080 ftlbs to equal the 416Rigby (handloaded-to-potential). Some 338WM can do that safely, but it is a max load that may be out of reach of some rifles (mine are usually loaded to 3900-4000 ftlbs). Practically speaking, that formula is about right since my favorite 416 load is 2825fps with a 350 grain bullet of SD .289 which is pretty much identical to a 338WM 225 grain at 2810 and an SD of .281. And you are correct about the 30 calibre. The 300's only need 3400 ftlbs. to equal the handloaded Rigby, and they are typically loaded to 3400-3600 ftlbs.

Karl

One of the reasons that CZ puts a pressure limit on their .505's is that most cases will fail at higher pressures.

Cases designed for the cheytac have a smaller internal volume (because they have a much thicker case head and walls) than 'standard' .505 brass - and loads are probably not actually interchangable.

Having watched them 'proofing' .505 cases at the Norma factory I know they don't bother to test them above 50,000 psi and just see how many loads they can get at that pressure.

With 'soft' cases like the current Norma or Bertram, you shouldn't have a catestrophic failure loading up to over 60,000 PSI but you will have poor case life.

Karl- Have we answered your question satisfactorily? I reiterate my first response. No problem. The Cz550 is a stout action and you have nothing to worry about.-Rob

quote:

Originally posted by 416Tanzan:
I'm just not sure what a full-power Gibbs would feel like in a normal walk-about rifle (no muzzle break, no recoil absorbing stock, under 11 lbs. fully loaded and scoped).

It would flat out hurt!

Several times in recent weeks I shot between 45 and 60 rounds over a couple of hours from a standing bench while testing different powders. We were looking for loads to duplicate original factory ballistics. We finished each session when we ran out of sized cases, and had to go home to resize and prepare the fired cases for another session. After that many shots I was happy we ran out of cases to load. Usually we returned the following week after my shoulder had recovered. Once I made the mistake of going back the next day to fire a few more loads out of my rifle, and with the tenderness from the previous day I packed it in after 6 shots. Most of those loads would ahve been around 95 to 100 ft lbs of recoil. Multiplying the recoil by about 1.5 would add considerably to the "felt" part of the felt recoil equation.

quote:

Originally posted by Robgunbuilder:
Karl- Have we answered your question satisfactorily? I reiterate my first response. No problem. The Cz550 is a stout action and you have nothing to worry about.-Rob

A question for you Rob.
With your experience how would you rate the various 505 actions for strength. The CZ550, the Heym, the Granite Mountain Arms, the M17/P14 Enfield, and any others that are commonly used?