09-17-2019, 08:19 PM
Growler Wrote:OP - It probably wasn’t anything you did or didn’t do.
Keep in mind you can take a superbly designed part with specs that should ensure ideal process and still have failures.
Take the best manufacturer out there, ship them a few bolt stock forgings with some voids or inclusions hidden in the material before machining, get the heat treat temperature profile out limits due to a shift change, undetectable failures will occur. A proof load followed by mangaflux will not catch every defect. Few (maybe none?) of our bolts are 100% tested, but typically batch tested, auditing just a few parts per lot. The cost of 100% NDT (non-destructive test) is just too high.
Short of aerospace-level QC (which you will never see in any of these parts), failures will happen. If more of us had higher round counts, we?d see this more often.
* Don’t use another bolt from the same lot
* If another bolt fails with the same barrel, the barrel extension and carrier geometry may be suspect.
* Lapping the receiver with hand tools is hardly a precision job, but it’s low-hanging fruit. If it makes you happy, like collecting headspace gauge sets, go for it!
My 2c? Pick up a group buy bolt, do whatever else gives makes you comfortable, and get back to the range
Well said brother.