I inherited my grandfathers bring back type 38 a few years ago. From my limited research, it seems to be a "school" rifle. It has the double 0 before the 163,754 serial number and school mark on the top of the bbl. Im hoping someone can tell me more about the barrel proof marks. I've read the there should be a circle with a triangle, which there is, and either an "S" or "B" proof mark as well. Mine looks more like a "<".

Any help would be appreciated.

Would need much more to go on than that 1 pic...take pics of the receiver, top, and left side especially, and some overall pics....

Thank you. This is what I know about the rifle. My grandfather brought it back from the  Philippines after WW2. He was a tail gunner on a B-24 at the end of the war. I have the bring back papers as well.
Here are some more photos. I'm curious about the barrel proof markings. Thanks again.

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Also, I know the wood was lightly sanded and "refinished", because I helped (in fact, begged) my grandpa do it in my youth. Ugh... Neither of us knew any better. Grandpa wasn't a gun guy. He never shot it. It's missing the floor plate, follower, and magazine spring. I hope to shoot in the near future.