22 LR Super X split brass?

[treefarmer]

Long story short, a very knowledgeable shooter friend came to our place to shoot a few rounds with a grandson that is going to Parris Island in the near future. I rode down to where they were shooting 3 different 22's, a Rossi pump, a Marlin bolt action and a Ruger Single-Six revolver. He said they had experienced some misfires and that some of the brass was splitting. New ammo from Walmart a few weeks ago. The misfires were in all the firearms so they are not the problem. Have any of you fellers ever seen this in new rimfire ammo? I've seen brass split in well used brass in reloads but this is new to me. Some of the cases split all the way back to the rim, my friend is sending some back to the mfg. for evaluation. The brass in the pic has about a 1/4" split and it lines up with the indention from the firing pin. Any thoughts?
Treefarmer

[swissk31]

It could be most of the priming agent settled on one side causing higher pressures on that side.

[DaveT]

I found this article a while back while researching various .22 loads....pretty interesting about how difficult it is to
manufacture .22 rounds...

CHECK IT OUT:

http://www.americanrifleman.org/article ... 2-rimfire/

[X711]

i've never seen that in 22lr and if it happened in 3 different firearms its obviously a ammo issue.
is that winchester super x? or who makes it?

[Bossman]

i've never seen that in 22lr and if it happened in 3 different firearms its obviously a ammo issue.
is that winchester super x? or who makes it?

Bump! Tfarmer what kind was it ?

[treefarmer]

Thanks for the responses and references. A friend pointed out the case in the picture is bulged, so I went where my friend was shooting and picked up several casings. Some were bulged and some were still straight sided, like out of the box. However I noticed that the straight sided ones all had the same strike mark from the same weapon(which ever one it was) and the bulged casings had a different mark from the firing pin. This leads me to conclude that one of his 22s probably has a bad chamber, thus bulging the casing and occasionally splitting a case. This does not eliminate the fact that the Winchester Super-X ammo had misfires in all 3 weapons. The weapons in question are a Ruger Single-six revolver, a Rossi pump (copy of one of the Winchester exposed hammer pumps) and an older Marlin clip fed rifle.
Here's one more picture showing the differences in the cases, the 3 on the left are not bulged or misshapen as are the 3 on the right.
Treefarmer