CZ USA 457 American Suppressor 22 Long Rifle Ready Blued Bolt Action Rifle - 20.5in - The classic American-style rimfire rifle, the 457 has a 20.5in barrel with no sights and is meant to be topped with a scope. Like all of CZ's 457's, it has an 11mm dovetail milled into the top of its receiver for attaching scope ring/mounts. This suppressor ready model features 1/2x28 threads and a black synthetic stock.