.22 LR case head separation

[Ironbear]

Had a case head separate on a .22 today. Never seen that before.

Split case on left. Same case on top right. Another, non-separated one for reference, on bottom right.

Son got his cheek sprayed. Next round in magazine blackened. No indication of previous squib (steel is nice feedback). Bore was clear.

Safety glasses object lesson. Be safe out there. Wear the glasses.

[xd ED]

Bolt gun, or semi auto.

Wondering if it fired out of battery....

[Ironbear]

Bolt

[Holland&Holland]

Wow. Never would have thought that possible with a 22

[Ironbear]

Played with the bolt and trigger. The bolt appears fully closed about 1/3 of the way through the downward motion. After about the 1/2 way point, the bolt "snaps" towards the fully close position. Pulling the trigger in the first 1/3 ends up just not engaging the sear and doing nothing. Only toward the end (maybe < last 1/4) will the hammer drop when the trigger is pulled. Out of battery seems like it wouldn't really work.

Though about head spacing. Fired case rims really aren't thicker than unfired ones. If anything, the fired ones seem slightly thinner.

Personally, I am thinking an annealing failure, that resulted in cracks at the bend.

[Rip Van Winkle]

How old is/was it? The case heads look like they've been bouncing around in someones pocket for a few years.

[Ironbear]

Unclear as to how old, but they came directly out of a 333rd Winchester bulk box.

Other than the blackening of the split one, the case heads look pretty good. I think the pictures didn't have good lighting and picked up some compression artifacts when I enlarged them. Hard to get decent macro photos, holding by hand.

[Rip Van Winkle]

The only thing I can think of is the brass was either improperly drawn, or harder and more brittle than usual.

[hard h2o]

As was mentioned probably out of battery.

Has the chamber been cleaned recently to remove any carbon ring?