Alaska Arms lever rings fit the Brno 602 Magnum action and the CZ 550 Magnum action interchangeably.
I prefer them over other brands however, on Model 98 Mausers, I have used the old fashioned - original Talley brand lever rings on their bases (milled blocks of steel) with perfect success.
If Talley presently makes rings for the factory milled square bridges on the 602 and the 550, I would bet they work fine as well.
As akrifleman points out, according to some folks, the CZ 550 millwork was not always super precise.
I’ve heard it from others as well so, I expect it was true.
Personally, I did not experience any such problems with the several 550’s that I used to own.
But, mine were from earlier production Model 550’s, both Magnum and Standard calibers.
The 6.5x55 that I kept (factory stocked carbine, Model “550 FS”) is one of the most accurate rifles I’ve ever owned.
I suspect the milling problem was when CZ’s equipment was wearing out, just before they quit making the otherwise excellent 550 series of rifles.
That said, a professional Gunsmith more than likely could easily re-cut the notches to fit.
