I was really impressed with the design features, reliability, and shape/proportions of the stock of the CZ457 American I bought back in 2017. I'd read so much about these rifles having good accuracy that I was really disappointed with mine, having shot it with several lots and grades of SK & Lapua ammo and never getting any decent groups at 50yds. I continued shooting with it, as some of the guys over on RFC mentioned their CZs required extended break-in before accuracy improved. After examining the ragged factory muzzle crown with a Hawkeye borescope, I pulled the OEM bbl and re-cut the muzzle with a precision 11* crown, which made for slight improvement, but it was still far from good enough to make me happy. Eventually I ordered in a Shilen ratchet #5 contour, parted off the heavy shank, cut the tenon to be a snug fit in the 457, used an EPS reamer and set it up with .042" headspace, cut the extractor slots on my mill, and glued it into the action with #609 Loctite. The Shilen was about 1/2lb heavier than the factory bbl, and I did have to open up the factory wood stock's bbl channel a bit by sanding to get it to fit, but I've now got a good looking sporter that shoots at least as good as it looks.
A few months later, I ordered in a 457 VPT with the Manners stock, and had bbl issues again, though this time, the 50yd accuracy did actually improve over the course of firing 500+ rds of SK through it. But when I backed off to 100-200yds, it fell on its face, so was treated to the same Shilen therapy - only this time, I went with a .920" straight bbl. Again, the results were worth the effort. I own four Vudoo repeaters (3 Gen 1s & a 360), a Rim-X, a couple of nice Anschutz sporters, a Sako P94S, Rem 541T - and these two re-barreled 457s are still my favorite light factory rifles, though the Vudoo Gen 1 sporter I built with a Krieger #4 sporter bbl in a Manners EH-2 stock will out-shoot the CZs by a slight margin.