My 858 is dead!

[Nisser17]

Why do people worry they are going to break a firearm?
Damm things are made to go bang, the CZ should be rock solid for 1000's of rounds before any new parts are needed. Was it NEA that had a15000 round count without a major problem?

I have about 2200 down the pipe on mine and no problems.

 

[dimeN]

tempering colors
on 2nd chart
http://www.engineeringtoolbox.com/tempering-colors-steel-d_1530.html

they are also not accurate... color can vary pending the alloy

also tempering temps should be held for a length of time... ( time at temp ) just raising the oxide colors is not dependable

according to wiki ... the temp for nitrocarburizing is high... and would definitely temper and soften the prior heat treatment

i've seen the youtube vid where a dude heat the receiver with an induction heater... quenches it in oil... then tempers it in oven prior to pressing the barrel in

my guess is that when they figured out the problem... all the did was re-heat treat the area in question ... and re-temper to spec.

 

[antiqueguy]

all I got to say is people cant leave good enough alone if lazy people would have not got this job done and just clean the gun after using surplus or reload you would not have parts going soft or worse getting brittle

the CZ is a easy clean if you take both hand guards off and the internals off you can put the muzzle into boiling water that go's above the gas block putting a swab or patch from the breech and pumping water through the barrel will get rid of the corrosive salts eastern bloc guns are simple and cleaning them is simple

 

[Yukon1911]

Might be the Czech surplus being hot.. I fired about 500rds of Czech surplus through my SKS.. That may have contributed to the cracked bolt

Czech surplus seems pretty solid! The gun is also Czech so it should have no problem with that ammo. My Russian Tula 1954 eats Czech for breakfast, Russian for lunch and Chinese for Dinner...........No problems and its all corrosive, which that gun was made to shoot!

 

[P0WERWAGON]

wouldn't the headspace being out slightly cause this kind of wear, rather than the nitro coating? the lugs being able to jack hammer slightly at first causing the peening.

mine has 3000+ rounds through it, 2000+ after the coating was done, and still has good rails. first batch