What would you build with a CZ 550 magnum action?

[Muskox]

358 Norma.

 

[MLindsay]

500 A2

 

[BeeMaa]

@x84958 - I'm glad you are doing well, and the 450/400NE is typically used in a double or single shot rifle because of the rimmed case. I'll let you (and others of course) debate the ballistic advantages/disadvantages over the options you've laid out. But for a bolt rifle, the 416RIGBY or 416RM would be so close that the animal would never know the difference.

 

[KMG Hunting Safaris]

450 Rigby

 

[Riflecrank]

So, has x84958 not said what bolt-face he has on his action ?
Mighty trollish of him.

MLindsay has the best answer: .500 A-Square
That was the first one I did in 1999.
Soon after that I had a .375 RUM done on a CZ 550 Magnum.
My final trick will be the slickest of all:
.510 WIN MAG via chambering refinements of the .495 A-Square.
You can do it on a Winchester M70, but it really deserves the roominess of a CZ 550 Magnum.

Of the two dozen re-chamberings and re-barrelings I have done on 15 CZ 550 Magnum plus one BRNO ZKK 602 rifles/actions,
there is one I do not recommend:

.410/404 Jeffery Rimless Nitro Express
Size the 404 Jeffery brass in the 450/400 NE 3" die,
necking down from .423" bullet to .410" bullet.
Fire-form the weak shoulder before relying on it in the field.
Just plumb silly, leave the 404 Jeffery as is.

 

[Riflecrank]

x84958:
Doodling with AI graphs of recoil and SD.
SD is useful for comparing bullets of same construction and caliber but differing in weight, from same rifle chambering.
Not for flitting about
between chamberings and calibers.
Does remind me of a fun alleged AI image found at Field Ethos:

 

[matt85]

This thread has taught me something... I didnt know the 550 magum action came in two different bolt sizes. I had just assumed there was a 550 and a 550 magnum.

 

[whisk(e)y hunter]

There are actually two action sizes, both “Medium” and “Magnum”, and then from there a number of bolt face sizes that support the various cartridges

The absolute bolt diameters are consistent within the Medium or Magnum sizes though

 

[skydiver386]

This thread has taught me something... I didnt know the 550 magum action came in two different bolt sizes. I had just assumed there was a 550 and a 550 magnum.

There is the CZ550, sized for 30-06, 300 Win, etc. Can have .473 bolt face or .532 bolt face.

Then there is the CZ550 Safari Magnum, sized for 375 H&H, 416 Rigby, etc. Can have .532 bolt face or .590 bolt face. Rare examples have a .640 (Gibbs) bolt face.

 

[Jefferry404]

Bolt sizes are the same for the medium and magnum actions, 0.695”.
Sir Crank is referring to the bolt “face” that can be std, magnum or Rigby head diameters. 505 Gibbs
Head diameter is .640”, folks think this leaves a rather thin rim.

 

[Jim Golden]

.460 Weatherby

My P14 Enfield is already barreled with a 26" McGowen barrel and chambered for this. Will be my second Enfield

 

[Brett20mm]

If you want to go "All Out" 600 Over Kill. My first CZ-550 is going to be 550 Magnum.

 

[whisk(e)y hunter]

If anyone needs some 550 projectiles feel free to reach out, I have a ton of Cutting Edge Raptors and Solids

 

[DmacD]

Confidence.
You will build confidence with a CZ 550 action. The calibre does not matter.

 

[John Telford]

If the bolt face is big enough then use the action wisely for a magnum cartridge.
500,404 Jeff can be built is “smaller” actions .
450 Rigby or 505

 

[coreydb]

What a wonderful conundrum! go with a caliber that has plenty of ammo availability. If you hand load, just pick your poison.

 

[86thecat]

Maybe pick a caliber and approximate velocity and let your smith decide what cartridge he can make feed reliably in that action. Not only bolt face, but feed rail design and how cartridges stack in the magazine determine how reliably it will feed. Anything for DG needs to feed and eject 100%.

 

[HunterX]

I haven’t heard anything like the 333 Jeffrey to be different. Otherwise, 350 Rigby for a Great Plains game rifle.

 

[Bonk]

I have a 300H&H built on a CZ550 Magnum receiver.

 

[Dublinpiper90]

For me it depends I’d go .505 Gibbs or a .450 Rigby for the heavy side on the milder side .404 Jeffrey, or just get one in .416 Rigby