3/25/2023 0 Comments Cz 457 mtr![]() ![]() Chambers that are too tight will cause the extractor to slip off the case rim when a live round is in need of extraction. Live rounds cycled through the MTR without any issues. ![]() The 457 MTR I tested engraved all bullets when the bolt closed, but it didn’t grab them so tightly that a live round wouldn’t extract reliably. Any yaw will manifest in larger group sizes, but the effects are amplified as distance to the target increases. The longer chambers that don’t engrave the bullet can allow the bullet to yaw prior to engaging the lands. Once the bullet touches the lands, it retains that orientation as it moves through the bore when fired. The advantage of having the bullet engrave when the bolt closes is the measure of consistency that lengthier chambers don’t allow. The headspace is considerably shorter than the rest of the CZ 457 models, so bullets are engraved with rifling by touching the lands when the action closes. (“CIP” is the European equivalent of SAAMI). In the MTR, CZ used the absolute minimum CIP-allowable dimensions for the rifle’s chamber. The big story for 2020 is the Match Target Rifle (MTR). The match-grade barrel is thick walled and cold-hammer-forged. ![]() The CZ 457 MTR is a precision rifle configuration with a premium walnut stock. Both polymer and steel mags are available between $27 and $36. The single-stack, 5- and 10-round magazines work well, too. In fact, the magazine hasn’t changed since CZ developed it for the CZ 452 all those years ago. What CZ hasn’t done on the 457 is change the magazine, and for that I’m thankful. The CZ 457 has a 60-degree throw giving the bolt handle plenty of clearance when cycling the action. Putting a 90-degree bolt throw on the CZ 455 often placed the bolt handle so close to the scope’s ocular housing that it was hard not to scrape your fingers when cycling the bolt, especially when the scope had lots of magnification and a large ocular housing. Rimfire actions are smaller than centerfire actions, which means that receivers have smaller diameters and bolt handles get shorter. However, in the case of the 457, the 60-degree bolt lift offers a real advantage. The downsides of each are that 60-degree throws usually have a heavier bolt lift, but a 90-degree throw feels slower when you’re in a hurry. Normally, I think the difference between a 90-degree and 60-degree bolt throw is negligible. The other significant improvement CZ made with the 457 is the 60-degree bolt throw. Minimizing sear engagement gives the trigger a zero-creep break, but too little engagement will cause the rifle to fire when the bolt closes, or possibly when someone jars the rifle. If jarring the rifle won’t cause it to fire, there’s probably enough sear engagement to guarantee its safe operation. Even when a quick bolt-cycling will cock the firing pin, the owner should smack the empty rifle on its butt (with the muzzle in the air) to see if the sear slips off. If there’s too little engagement when running the bolt fast, it won’t cock the firing pin. That’s about as light as they go.Īdjustment of sear engagement on the 457 is highly desirable, but should be done in small increments. The rifle ships with the trigger set at around 3 pounds (or a little over) and, after a few minutes work, I had Guns
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