1:16.5 twist for 416 Rigby 400gr bullets

[hammz]

Hello everyone, new member here. I am seriously looking at a CZ 550 Safari Magnum in .416 Rigby. While I'll likely never go to Africa to hunt, I do plan on using it for large North American game like elk, moose, and possibly bear one day. I previously had a Winchester Model 70 in .416 Rem Mag that I loved to shoot, and it was an MOA gun at 100 yards. I got rid of that to get a Ruger No. 1 in 416 Rem Mag, but figured a single shot may not be the best in the world especially if I do find myself in bear territory with it one day.

I looked at the 458 Lott, but it is way overkill for anything I'd use it for. Perhaps even the Rigby is a bit. But I do love the 416 caliber rounds and while I don't reload now, I like the thought of being able to squeeze more juice from the Rigby one day if I do reload vs. the Rem Mag.

Sorry about the rambling, so back to my point. The only thing that is making me hesitate on getting the CZ 550 in 416 Rigby is the fact the twist rate is 1:16.5". My Winchester was a 1:14. I know you can go up to 450 grain rounds in the 416 calibers. So I am not sure if the 1:14" is to stabilize those, or if it's needed for the 400gr rounds. One thing I don't like being limited on is ammo selection, so I always usually opt for faster twist rates. Granted, 400gr is the norm and anything over that seems to be the exception when it comes to 416 calibers. If the 1:16.5" can easily stabilize the 400gr rounds then I'd be happy to get the Rigby, but if it'll have trouble or it can but is limited to the matter of picking the right bullet, then I may just get a 375 H&H Model 70.

 

[375 Ruger Fan]

I think you'll be fine with the 1:16.5" twist rate.

There was a recent thread on the same topic, but for a 404 Jeffery , which is extremely close to the 416 caliber (.423 vs.416). I recently converted a Win M70 from 300 RUM to 404 Jeff and the Krieger barrel was 1:16.

Link to the other discussion:
https://www.africahunting.com/threads/404-j-twist-rate.51527/

 

[hammz]

Thank you for the help! I found the twist calculator that you linked in that thread and it looks like the 1:16.5 pretty much stabilizes everything I tested with it.

 

[Hoss Delgado]

1:6 for a .416 is absolutely fine. It can stabilizile those 400 grainers easily .
CZ , and their older counterpart BRNO , make really good rifles. Do you have any idea what kind of loads you would want to run through it ? FMJ ? Monolithics ? Monolithic solids demand some extra consideration in rifle twists.

 

[hammz]

1:6 for a .416 is absolutely fine. It can stabilizile those 400 grainers easily .
CZ , and their older counterpart BRNO , make really good rifles. Do you have any idea what kind of loads you would want to run through it ? FMJ ? Monolithics ? Monolithic solids demand some extra consideration in rifle twists.

I actually was able to cancel my order for the CZ 550 .416 and am going to go with a Model 70 Safari Express in 416 Remington Magnum which uses the 1:14" twist. I didn't switch just for the twist, but also the cost of ammo was significantly higher for the Rigby as I was looking to buy some. I was surprised to find it was even costlier than 458 Lott ammo. Right now, I don't reload so for me the cost of factory ammo is somewhat important for the time being. I can buy almost 2 boxes of 416 Rem ammo for the cost of one box of Rigby ammo.

As for loads, it depends on the application. For target shooting and practice I'll use the Hornady 400gr DGS rounds which are what I shot a lot out of my Ruger No. 1 in 416RM. For elk I'd probably go with some 300gr or 350gr Barnes TSX loads, or a 400gr A-Frame. Then for bear or moose, probably the 400gr banded solids from Barnes.

 

[IvW]

The 375 H&H would be a much better choice for your intended purpose...

 

[Wyatt Smith]

The M70 Safari Express is a fine rifle. It should be ready to go out of the box, when I’ve read (only read) that a lot CZs need to see a smith to feed properly. I have handled a new CZ and the action was rougher than my Winchester. Enjoy it!!

 

[Hoss Delgado]

The M70 Safari Express is a fine rifle. It should be ready to go out of the box, when I’ve read (only read) that a lot CZs need to see a smith to feed properly. I have handled a new CZ and the action was rougher than my Winchester. Enjoy it!!

You read correctly , Wyatt. I noticed the problem , in the larger caliber ( above .375 HH Magnum ) ones , first hand. After a gunsmith fixes up the feed ramp , they do work perfectly though

 

[hammz]

Agree with both of you. I've had both, and can say first hand that the CZ actions are really rough out of the box. I've had a CZ 550 in 300 Win Mag, 375 H&H, and 458 Win Mag. The bolt loved to bind on all of them unless you pushed it in completely straight. Any amount of force on it that moved it slightly off center would cause it to bind. This was most surprising on my 300 Win Mag since it was a semi-custom CZ 550 (it was the CZ 550 UHR) and cost $1,400.

This isn't just an issue with the CZ 550s, either, it plagued every 527 I had as well. It just seems like all their CRF actions are super rough. Where-as I've heard that their new push feed actions are super smooth (the 557 series).

I do love the 550 series. They're very rugged guns, and built like tanks, and the single-set trigger is phenomenal, but the rough actions leave a bit to be desired. The Winchesters are built just as well, while having actions that are as smooth glass and more features for only $100 more.

 

[Hoss Delgado]

Agree with both of you. I've had both, and can say first hand that the CZ actions are really rough out of the box. I've had a CZ 550 in 300 Win Mag, 375 H&H, and 458 Win Mag. The bolt loved to bind on all of them unless you pushed it in completely straight. Any amount of force on it that moved it slightly off center would cause it to bind. This was most surprising on my 300 Win Mag since it was a semi-custom CZ 550 (it was the CZ 550 UHR) and cost $1,400.

This isn't just an issue with the CZ 550s, either, it plagued every 527 I had as well. It just seems like all their CRF actions are super rough. Where-as I've heard that their new push feed actions are super smooth (the 557 series).

I do love the 550 series. They're very rugged guns, and built like tanks, and the single-set trigger is phenomenal, but the rough actions leave a bit to be desired. The Winchesters are built just as well, while having actions that are as smooth glass and more features for only $100 more.

BRNO could probably use me as their advertising agent if they were still around , as l repeat this so much : Search for a nice ZKK602
To me , it's THE rifle action .
I own a beautiful .350 Rigby Magnum on a ZKK-602 action and it's my best purchase !

 

[hammz]

BRNO could probably use me as their advertising agent if they were still around , as l repeat this so much : Search for a nice ZKK602
To me , it's THE rifle action .
I own a beautiful .350 Rigby Magnum on a ZKK-602 action and it's my best purchase !

I did some quick digging and found some. They seemed to be priced similar to the CZ 550s. They look pretty much identical aside from the action (I can see it has the 3 position safety which is nice). Was BRNO owned by CZ at some point? I remember seeing CZ selling a BRNO Stopper rifle at some point, as well as saying their 550 Magnum is known as a 602 Brno. Or was CZ an importer for BRNO?

 

[Hoss Delgado]

I did some quick digging and found some. They seemed to be priced similar to the CZ 550s. They look pretty much identical aside from the action (I can see it has the 3 position safety which is nice). Was BRNO owned by CZ at some point? I remember seeing CZ selling a BRNO Stopper rifle at some point, as well as saying their 550 Magnum is known as a 602 Brno. Or was CZ an importer for BRNO?

BRNO eventually became CZ.
The BRNO ZKK-602 is the predecessor of the CZ 550. In my opinion ( and the opinion of a few others on these forums ) the ZKK602 action is FAR better than the CZ 550. I once got into a hot debate with some of the other members on these forums about my view. But with all due respect to them , l will stick to my opinion. The ZKK-602 was originally offered in .375 HH Magnum , .358 Norma Magnum and .458 Winchester Magnum . To me , this is the rifle of all rifles . You can use a ZKK-602 action for building a .458 Lott , a .505 Gibbs , a .500 Jeffery , a .404 Jeffery ... The options are endless. The best ones the the ones made before 1978 , which had a little pop up peep sight... Like Mine.
Not bashing the CZ 550. They are great guns. But l am not ashamed of admitting that l like my ZKK602 far better than any CZ rifle. I have an extra BRNO ZKK-602 action which l plan to use for building an 11.2 × 72 Schuler rifle some day.

 

[hammz]

That's a really nice rifle! What does it weigh in at? It's pretty sleek looking.

And yeah, I love CZ rifles and I don't want to come off like I am bashing them. They're built like tanks and will last forever, but they just have a certain "roughness" to them, where-as something like the Model 70 just feels more refined. I wouldn't go as far as to say the Model 70 is better built than the CZ 550. They're about equal in that regard. Both have insanely strong actions. It's just the Model 70 feels like it has that extra polish and refinement put into it at the factory that the 550 doesn't have.

 

[Hoss Delgado]

That's a really nice rifle! What does it weigh in at? It's pretty sleek looking.

And yeah, I love CZ rifles and I don't want to come off like I am bashing them. They're built like tanks and will last forever, but they just have a certain "roughness" to them, where-as something like the Model 70 just feels more refined. I wouldn't go as far as to say the Model 70 is better built than the CZ 550. They're about equal in that regard. Both have insanely strong actions. It's just the Model 70 feels like it has that extra polish and refinement put into it at the factory that the 550 doesn't have.

My ZKK-602 weighs 8 pounds . Probably an ounce or two more after l added a rubber recoil pad . It is barrelled for .350 Rigby Magnum , regulated for a 225 grain Kynoch bullet . I bought it from a friend . I would consider it to be even one step above the much revered Mauser 98 action . It is extremely flat shooting and recoil is very , very manageable . The weight is very comfortable and l will never let go of it.
I also own a pre war Winchester Model 70 in .375 HH Magnum . Great gun. But let me tell you something from personal experience . They are not as refined and flawless as pre 64 Winchester Model 70 fan boys will have you believe. A lot of work needed to be done to the feed ramp to make it feed soft nosed bullets reliably. Also , the stock split and has been repaired with Stove bolts and epoxy ( plus minus epoxy , l believe ) . It is a gift from my granddad , who used this gun to take a Bull elephant in Kenya in '68 using a shoulder shot.
There is one very big advantage of the pre 64 model 70 Winchester over the new Winchester Model 70 . The pre 64 Winchester Model 70s in .375 HH Magnum hold 4 shots and 1 in the chamber. The new ones hold 3 shots and 1 in the chamber. So the old Model 70s have a Magazine capacity of one more round.
After l come back from my November Roe deer hunt in Sweden , l will see how much progress l make on my 11.2 × 72 Schuler rifle project on the ZKK-602 action