Very strange. Two broken bolts on two different rifles. Anyone have any thoughts or insights?
In your first post the issue was with a Century VZ 2008.
Is the rifle that is currently giving you problems a D-Technik/CSA Vz58 or Century VZ 2008?
Still a VZ2008. In searching for causes, I've come across only three other reports of the narrow lug breaking. Two were D-Technik/CSA rifles, and one was Canadian, maybe also made by CSA. I don't think the issue is with Century builds. There are several members here who have fired thousands of rounds through their tabbed VZ2008's without any problems. Back in 2014-2015 when VZ2008's were being sold by PSA, J&G Sales, and Atlantic Firearms, they would come in waves. I remember there were about 2,000 in stock with each vendor each time. Without going back over previous threads, I estimate that at least 20,000 VZ2008's were sold from 2008-2016. Maybe more.
The most common failure, although rare and also relevant to CSA and original Czechoslovakian rifles, seems to be broken firing pins, then after that, broken strikers and disconnector springs. I've seen very few accounts or videos regarding failures of the VZ58 platform, maybe 5% as many as I've seen about AR15's. I've seen about as many failure videos regarding AK's and SKS's, but as both those platforms were produced 100-to-1 over VZ58's, I have to admit that VZ58's probably aren't quite as reliable.
This bolt breaking problem seems to be very rare and not limited to VZ2008's. I'm thinking it may be just bad luck with surplus parts of unknown wear. Working on old cars, I've seen similarly unusual streaks of failures with used parts. If you have any insights or thoughts, however, I'm definitely interested.