550 Gibbs

[teklanika_ray]

I seem to have caught the "bigbore bug", and I can't seem to find a cure.

Here is the background. I bought 5 CZ550 from Wayne at AHR. I am currently having the following guns built:

- 550 Magnum (built on a CZ550) that Neal Sherlie developed 20 years ago, I think this one will be a gunsmith build. The barrel is ordered (4-6 months wait from PacNor [I could have sworn that wait was in weeks when I ordered two barrels from them, but it was confirmed months yeaterday], I recieved the custom Manson reamers and go nogo gauges this week, custom reloading dies from CH4D should be in this week, I got my order of 700 grain Hawk bullets this week, and should be getting Brass and Bullets form Mr. Sherlie today. Seems like I am waiting on barrels, and the Richards Microfit barrel).

-550 Express also Neal Sherlie (built on a VZ24 with a Richards Microfit Wolverine Style stock. This one I'm building myself)

- 505 Gibbs (built on a CZ550 Magnum, built by Bayou Weapons Systems).

- 416 Rigby (built on a CZ550 Magnum, had Doug at Doug's Gun Repair barrel the action, and bought a BRNO ZKK 602 stock to put it into, I like the wayit looks).

- 458 Lott (built on a CZ550 Magnum, had Doug at Doug's Gun Repair barrel the action, and bought a BRNO ZKK 602 stock to put it into, I like the way it looks).

During this process, I stumbled onto a reference to the 550 Gibbs magnum and the 550 Ivory Express. I also learned a lesson to ask here, before buying custom reamers, dies, and such!! Does anyone have any information on either of these cartridges (links, books, reloading data, ballistic, and points of contacts for someone who has one or has built one)?

I have the "bigbore bug" bad, and I think I just have to ride it out. I just bought a CZ Safari Classics action on Gunbroker this morning, and it feels like a 550 Gibbs magnum to me. I'd like to make sure there is water in that pool before I dive into it though.

Thanks in Advance!!
Ray H

 

[Jefferry404]

Ray,
Probably someone was thinking cz 550 Gibbs conflated things.necking the Gibbs to 510 has some concerned (I am thinking about a 505 Gibbs +P)
For the 550 magnum gunsmith you might check with Tim at Matrix Gunsmithing in CO. He finished a pair early last year using cz 550 actions on cz wood stock and the B&C stock using PacNor barrels.
PacNor was 2 months but are having machine problems and barrels are tending to 6 months

 

[teklanika_ray]

Ray,
Probably someone was thinking cz 550 Gibbs conflated things.necking the Gibbs to 510 has some concerned (I am thinking about a 505 Gibbs +P)
For the 550 magnum gunsmith you might check with Tim at Matrix Gunsmithing in CO. He finished a pair early last year using cz 550 actions on cz wood stock and the B&C stock using PacNor barrels.
PacNor was 2 months but are having machine problems and barrels are tending to 6 months

No, I'm certain it was a 550 Gibbs reference. I'll see if I can find it again and post it here.

For now, here are two clips from the same gun on YouTube. It is supposed to be a 550 Gibbs Magnum. It is a beast of a firearm, but the recoil does not look off putting.

 

[Jefferry404]

Could be, looks like enough shoulder to headspace but unlike the 550 mag, with Weatherby case pressure is much lower.
Can gin up a design if you are interested?
Steve

 

[teklanika_ray]

Could be, looks like enough shoulder to headspace but unlike the 550 mag, with Weatherby case pressure is much lower.
Can gin up a design if you are interested?
Steve

Really, that would be interesting. What would you need to get started?

 

[colorado]

Best of luck! My CZ 550 in 500 Jeffery is enough for me. As Clint said "A man has to know his limitations"

 

[AustinM]

The 550 Gibbs has already been designed from my understanding. I believe the gentleman that created the 600 Overkill (RobGunBuilder on most forums I believe). He should have some information, or find some forums that he is apart of, as I have seen it mentioned before.

 

[teklanika_ray]

The 550 Gibbs has already been designed from my understanding. I believe the gentleman that created the 600 Overkill (RobGunBuilder on most forums I believe). He should have some information, or find some forums that he is apart of, as I have seen it mentioned before.

Thx for the information.

 

[krish]

Thx for the information.

Neal has info on 550 gibbs. That is whom I got the brass from.
Krish

 

[teklanika_ray]

Yes, I talked to him a little bit. He has a reamer and a barrel he was going to build. I just hit him up so much on the 550 Magnum, I don't want to wear out my welcome. I just got some brass and bullet from him today as a matter of fact. Thanks for referring me to him by the way. Also, did not want to impose on you to much either, but I was certain you had mentioned it in an earlier conversation. I bought an action this morning on gunbroker just for this project. I can't get it out of my mind.

 

[Flewis]

There was also a 530 Gibbs.

 

[teklanika_ray]

Neal has info on 550 gibbs. That is whom I got the brass from.
Krish

Krish, do you actually have a 550 Gibbs?

 

[teklanika_ray]

Well, I blew out a 505 Gibbs and seated a .550 700 gr Hawk bullets in it. It doesn't leave much shoulder, but it looks usable. I will try calling Neal and asking him for more information. I think he knows the guy in the video. Maybe I can get a name for him.

 

[Jefferry404]

i went with a 40deg. shoulder (between the gibbs and rigby) and a slightly tapered case (about the same shoulder height as the gibbs). Case capacity was 201gn H2O. when fitted to a-square gibbs data, with a 700 gn Hawk, gives 2150fps with 24" barrel at Maximum Gibbs CIP pressure. Case wall is thinning on the low side.
Mr. Ray, if you could measure the case wall of your firefomed gibbs to 550, would be helpful going forward.
Steve

 

[Daniel Cary]

I've heard of member's 550 magnum. (there's a fakebook page dedicated) and the 500 MDM: these both seem a breed apart.

The Jeffery, however, is a menace

This is a member's MDM here, if I'm not mistaken .. gives recoil a perspective: damn