Doesn't look like an AI case to me. With the primers blowing I'd suspect something wrong with the headspace. As suggested, check headspace and if it's excessive take a look at the back of the bolt and recess in the receiver where it locks in for wear or peening. If that checks out okay, then it's a chamber problem. Would make a great candidate to send to JES to turn into a .38-55 pump thumper.

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