New switch barrel project with .590 and .640 bolts ?

[hemiford]

Before I delve into this project headfirst, I thought I would ask here.

Does anyone know of a custom action that uses bolts, two separate bolts
of course, having the Rigby/Weatherby/Lapua boltface and also a bolt having
the Gibbs/Chey-Tac boltface (for the same receiver) ?

I'm considering a switch barrel (and switch bolt) rig, to handle certain ammo
in each of the above cartridge families.

******

I think it was both BAT and Stiller that told me NO.

 

[MagnumManiac]

You could have a bolt built from a factory rifle to do what you want.
I have a CZ 550 from the custom shop in 505 Gibbs, not much metal is left at .640, but enough to function. I also have a CZ 550 in 416 Rigby, the action requires considerable alteration for the 505 to fit, the mag box needs extending, the rear bridge requires opening/notching for the case to eject.
The Granite Mountain action may be a better candidate, but it is expensive.

Hope this gives you an idea on the difficulty of what you want to do.

Cheers.
gun)

 

[HarryN]

Does it need to magazine feed or is single feed ok ?

 

[hemiford]

Thank you, gents.

Harry, I'd be happy with single feed, although mag feed would certainly be
frosting on the cupcake. But honestly, I likely couldn't take advantage
of a mag feed anyway on these big bruisers.

Magnum, what do these GMA actions cost, do you know ? I guess I should
just call, I have other questions also.

Is the CZ 550 action bigger/stronger than a Weatherby ? Bolt diameter, etc. ?

 

[MagnumManiac]

The Granite Mountain action is very large, it is designed for the 505, it has a .750" diameter bolt, action length is longer than a CZ 550 and it is mammoth in size and weight, they run around $3,500 for a bare action.
I believe, not sure, that the CZ 550 action is longer than a Weatherby MKV, the CZ's bolt is .700" in diameter.
This is my personal opinion, any CRF action is better than any PF action when dangerous game cartridges are in question, I have never been a fan of Weatherby rifles, their cartridges, yes, but not their rifles.
I have several CZ's, and I like them very much.

Hope this helps.

Cheers.
gun)

 

[Deleted member 46119]

I don't know the CZ 550 in person. I know the Weatherby pretty well.

CZ vs. Wby I'm not sure about which is stronger. Design differences vs. metalurgy.

Not sure which can take a longer cartridge. I know a Wby can to 4" and with work eject a loaded round without releasing the bolt stop.

The CZ is available in a 505 Gibbs so getting a second bolt is probably not that hard. Plenty of meat left around the case head.

I can't remember how much was left when I measured out the Weatherby to investigate a 505Gibbs based design but it's not much.

In order of my understanding of which will take a 505 Gibbs bolt face:
Hall single feed (I have a repeater) bolt is .750 at the breach.
Stiller Tac 408
CZ 550
Weatherby

Of course there are others.

I think Swamplord said he uses CZ for the Mjolnir

 

[hemiford]

OK, thank you all again ! I'm off to do research.

One last question for the moment: I can see no theoretical reason why a
properly set-up CRF rifle cannot be as accurate as a properly set-up PF rifle.
Am I correct ? (Thinking here of the CZ 550 action)

 

[MagnumManiac]

My opinion is not based on accuracy, only function. There really is no difference other than the CRF action has more control over the cartridge, and the large claw extractor never fails to extract a cartridge, IMHO and experience. I do have both designs, but none of my DG rifles are push feed.
Maybe because I don't use my PF actions as repeaters normally, I have had the situation where I double fed a round when spotlighting, which is no big deal, I hadn't closed the bolt on the first round and pulled the bolt back because the shot was lost, then when another presented, I fed another shell in, which jammed the rifle. I am so used to pulling the bolt back with the shell coming with it, that I forgot to close the bolt at half cock, then withdraw so the shell comes with it.
I wouldn't want that to happen hunting buff or ele, but everyone gets used to whatever type of action they use the most.
Strength wise, a CRF has more extraction and camming power than a PF, but that's about the only difference.

Cheers.
gun)