I have a LH CZ550 I picked up off here chambered in 375H&H with AHR trigger, 3 position safety, factory stock, etc. Nice rifle but the realization has set in that I have an affordable LH magnum option to build a 3.8” length big bore on...which is rare for a lefty. Since they don’t make the LH CZs anymore I want to use it for a new project.

As far as big bores go I have the 375 H&H, 375 RUM, and 458 Lott covered with other rifles and want to push it with this one. Rifle could see Africa one day but right now it’s more a question of want vs need...just can’t decide on chambering.

Kicking around the idea of the big .458 cases to push 550gr so it has less overlap with the Lott. Favoring the 450 Rigby over a 460 WBY at the moment. Or do I jump into the big 50s and go 500 Jeff or A2? 416 Rigby is also an option but lower down the list.

With 375's and a Lott, I think that the needed cartridge would be a 404 Jeffrey.

quote:

Originally posted by Fjold:
With 375's and a Lott, I think that the needed cartridge would be a 404 Jeffrey.

404 or 416 Rigby would be the most logical but rebarrelling my RUM would be a more feasible option to get to the 404 at some point if so desired.

There just aren’t many affordable routes to a lefty magnum action like the CZ so want to utilize it accordingly.

The only real choice is to with a 505 Gibbs or 500 Jeffery, unless you go with a 450 Rigby and put the Lott to rest.

I have a LH CZ550 which has been converted to 458Win but have been thinking along the same lines as you. It's a rare large and long action for a lefty. I'll be running it as a 458 for a while but ultimately it may be rebarrelled to something larger.

Bertram make brass for what they call a 500 Weatherby, though the brass is only marked '500'. It's essentially the 460 Weatherby case with the neck opened up to take a 510 bullet. The difference between it and the 500A2 is the venturified shoulder and longer neck of Bertram's version, which to my mind are design pluses for feeding and using cast bullets. Quite a few of the large 500's have necks that are too short IMO.

Of course you can go to the 500 Jeffries or 505, but that doesn't leave a lot of metal in the bolt around the rim and besides, how much power do you really want or need? Something that can exceed 500NE specs would be ample power for me.

Do you want factory ammo availability as a criteria for a new chambering? If not, what would be wrong with a 458 Express, the biggest you go in length on the H&H case in 458 calibre and still can shoot the 458 Win and 458 Lott cartridges in the same rifle.

A kiwi hunter has followed this path when hunting buffalo and elephant, starting out with a CZ Brno 458 Win opening it up to the Lott and finally the full 3" 458 Express.

I have a full custom 375 h&h - I originally left the factory stock and hunted the gun hard. It was pretty worn out. Now it has a nice custom wood and will probably be my range gun.

I have a 458 Lott with factory wood. The Lott is wasted on me. My hunting maxes out at 375 h&h. I was thinking of putting a 375 barrel and make it a backup rifle. But I have too many blasers and ruger 375 h&h.

It’s a great rifle platform for Wayne to do his magic.

Mike

quote:

Originally posted by chuck375:
The only real choice is to with a 505 Gibbs or 500 Jeffery, unless you go with a 450 Rigby and put the Lott to rest.

I don’t think the Rigby puts the Lott to rest...I think it just picks up where the Lott leaves off at lower pressures. Could run 450s and 500s in the Lott at reasonable velocities and then build the 450 Rigby with the idea of 550s at 2100ish and reasonable pressures and approaching performance of 500 Jeff. I’m ok with a bit of overlap on rifles.

The 500 & 505s are intriguing though.

375 300gr at 2550 in H&H
375 350gr at 2500 in RUM
458 500gr at 2200 in Lott
458 550gr at 2100 in Rigby

An animal will likely never know the difference but it’s fun to think out loud.

quote:

Originally posted by eagle27:
Do you want factory ammo availability as a criteria for a new chambering? If not, what would be wrong with a 458 Express, the biggest you go in length on the H&H case in 458 calibre and still can shoot the 458 Win and 458 Lott cartridges in the same rifle.

The .458 Express 3-Inch is a ridiculous bit of wildcatting masturbation.

A kiwi hunter has followed this path when hunting buffalo and elephant, starting out with a CZ Brno 458 Win opening it up to the Lott and finally the full 3" 458 Express.

The Kiwi would have been better off leaving well enough alone.
The SAAMI/CIP-chambered .458 Winchester Magnum can be "wildcatted" by loading it LongCOL.
It will outdo a "no-throat" .458 Express.
It can be loaded to 3.780" COL with a 500-grain Barnes TSX crimped on the 5th cannelure, secure as hell is hot, at 3.780" COL,
and make bugholes at 2250 fps, and exceed 2340 fps MV in a 25" CZ barrel.
Accuracy may be better at submaximal velocity, depending on the accuracy node of your rifle, or the shooter's flinch?
Really now, 3.000" brass in a 3.800" magazine box is a colossal cluster that performs poorly when throated short.

I like the forerunner .450 Dakota better than the .450 Rigby me-too.
Get brass directly from Dakota Arms.
About $1.80 per piece of brass last time I heard. Made by Norma and excellent.
It is very nearly the 460 WBY with the belt turned off and a more conventional shoulder of 26 degrees.
The .450 Dakota has a slightly bigger case capacity (by 4 or 5 grains H2O) than the .450 Rigby which has a 36-degree shoulder.
Nostalgia for the late-comer .450 Rigby is a false nostalgia.

Build a .475 or .510-caliber rifle if you want different.
But the .458 WIN works wonders in a CZ 550 Magnum.
Mine is a 6-shooter very comfortable with 500-grain TSX at +2300 fps, when loaded LongCOL.
Outclasses the SAAMI/CIP .458 Lott, easily.
A leftie CZ .458 WIN LongCOL would be neat.
Can a leftie B&C "Kevlar/Aramid" stock be had?
I only shoot my .450 Dakota at 2350 fps so as not to be hard on the pretty wood.
The CZ .458 WIN LongCOL does very nearly that with the 500-grain TSX.

Rip ...

quote:

Originally posted by RIP:

The .458 Express 3-Inch is a ridiculous bit of wildcatting masturbation.

The Kiwi would have been better off leaving well enough alone.

Rip ...

So is wildcatting, or masturbation as you now call it, only the domain of those living in the good old USA.

So, you have no meaningful
justification for the .458 Express?
Just identity politics?
What are you?
An American Democrat?

Rip ...

quote:

Originally posted by RIP:
So, you have no meaningful
justification for the .458 Express?
Just identity politics?
What are you?
An American Democrat?

Rip ...

The hunter in question opened up his Brno to the Express cartridge which gave him good velocity without compressed loads at lower pressure with a cartridge that didn't slap around in the mag box. He was happy with that.

One could argue that the majority of wildcats serve no real purpose that established cartridges don't already provide but each to his own and life would be pretty boring without those wanting to experiment.
Many don't like the 458 Win and prefer the Lott or something else, that's their choice. I don't have any skin in the game, I just pointed out that there is another option over the 458 Win or Lott on the same case platform.

The politics as you call it is that hunting doesn't begin and end in the USA, there are just as many hunters around the rest of the world who experiment in wildcatting, I don't see why you had to get so vitriolic over mention of the 458 Express. However how you react to others opinions is your problem not mine

I had a RH Model from the custom shop in 505 Gibbs, with a 600gr Woodleigh at a little over 2300fps, it was too much fun for my injured shoulders. I could handle the same bullet at 2050-2100fps, but even that in a 9lb big bore was stiff to shoot.
Just for nostalgia sake, that’s what I would build again, but it would have to weigh more than 10.5lbs for my liking. My 500NE 3 1/4” double is almost 14lbs, doesn’t kick at all in comparison.

Cheers.

I have a CZ 550 in 500 Jeffery. It has two mecury recoil reducers in the stock. It weighs 11.25 lbs. Just right, nice offhand, a little sporty off of the bench. Don't notice the recoil at all hunting.

The 450 Dakota with Cup Points is an absolutely deadly combination on buffalo...based on my experience. Will flat out put them down!

ROSCOE,

Is that a 450-grain or 500-grain North Fork Cup Point?
And at what velocity, in your .450 Dakota, that is so effective on buffalo?

Rip ...

Talked it over a bit with Wayne at AHR and have decided on the 500 A-Square for the project. The 50s give enough separation from the Lott and the 500 Jeff is a bit short and the Gibbs is just too big. A-square seemed like a reasonable compromise. Going to be a bit of a wait but will likely be worth it. Gives me plenty of time to start pulling components together.