Gunsmithing CZ 550 Magnum Action accuracy potential for long range 338 Norma Magnum

[Ruansmal]

I’ve got a brand new CZ 550 Magnum 416 Rigby action lying around. Has anyone built a long-range rifle on one of these actions and what accuracy can one expect out of them? I was thinking of building 338 Norma Magnum. What futures of the action makes it less accurate compared to a custom action like a Stiller? Can this be overcome and how?

 

[gol1]

I know that George from GAP was using them to build 0.33LM rifles with great success, maybe you should contact them
Anyway great and strong action a little slow on the lock time but it can beslved easily with replacement parts you can get from brownells.
Good luck
Gol

 

[MikeeBooshay]

If you decide you don't want to play with that action, I'd be interested in acquiring it, as a 416 Rigby, for a hunting rifle I have in mind.

 

[Stokes]

I had one of the 550 338 Lapuas that George did.
While it did EVERYTHING well (function and accuracy), I just didn't like it much. Mine still had factory bottom metal (very functional, just didn't like it), and it just seemed too much like a hunting rifle trying too hard. Admittedly, all my complaints were pretty superficial, but then again, I don't have an ugly girlfriend.

I'd probably use a different base for a tactical style gun if I were to do it again.

 

[UA_Flyfisher]

The 550 actions see a ton of praise in the hunting world and particularly in the big magnums but they are somewhat of an anomaly in the Long Range game. Biggest questions would be if you needed it to work with a mag system and the lack of stock choices. GAP built some awesome 338 Lapuas on those actions in the early days using custom inlet McMillans but I think all of them used the factory bottom metal. I'm not sure if the CZ action can be adapted to a AI DBM. One other issue is scope mounts, USO and Ken Farrell used to make 20MOA rails for the CZ actions but they are probably a special order item now. That leaves you with the CZ rails and a small selection of compatible rings. Otherwise from a strength and accuracy standpoint you give up very little to most other actions.

 

[MikeeBooshay]

One other issue is scope mounts, USO and Ken Farrell used to make 20MOA rails for the CZ actions but they are probably a special order item now. That leaves you with the CZ rails and a small selection of compatible rings.

Otherwise from a strength and accuracy standpoint you give up very little to most other actions.

I've got one in 375H&H, it is a hammer - shoots sub 1MOA after being reworked ( added pillars, rebidded action and barrel, added cross bolts, trigger work), I'll look around for the test targets, but it was surprisingly good, with factory barrel.

One interesting thing on these rifles, the barrel also has an integral recoil lug, in addition to the action lug. And it won't shoot well, without that lug bedded as well. The stock pillars, were,,,,, tubing, and too short. Fixing all that, made a 2-3 inch rifle into something special. I like having a six round dangerous game rifle, with controlled round feed, and a set trigger if you want.

On mounts, as long as you aren't requiring pic rails, Talley makes plenty to choose from that fit and are good solid mounts.

 

[Ruansmal]

This is how my 375 shoots out of the box...