I just got my grandfathers(I think) Arisaka type 38 rifle. I hardly know anything about it. I just know that he was in the navy, and was in japan at some point. We have a letter that he wrote home from somewhere around hiroshima about 12 days after the bomb went off. Here are some pics of the gun. I can’t tell what the marking on the receiver means, I looked on this site: http://www.radix.net/~bbrown/japanese_markings.html
but it didnt seem to exactly match any of them 
Hi.
According Honeycutt/Anthony “Military rifles of Japan” this symbol can be found on training rifles only, but meaning unknown.
Can you please add pics of the other markings, too (especially of the markings on pic 1 in front of the “arsenal marking”)?
Yours
tom 
I didnt see any other markings on the whole gun. I’ll take a better look though. Where do you see another marking in the first pic?
I think what you’re seeing is just some small nicks and dents. I looked and didnt see anything. heres a couple up close pics I just took
If you guys search the forum you should find quite a bit on Arisake rifles. Let me know if you would like a thread to be brought out of the Archive room. 
found a couple other markings. a “211” on the stock, and some japanese text underneath
Hello,
yes Tom is right - its a trainer rifle - made to fire blanks or soft training rounds so called gallerie practice rounds. NOT FOR LIFE AMMO.
From the outer shape it resembles more a T 99 trainer. The receiver/tang assembly is made in one piece at so it is with the trigger guard/ tang assembly at trainers.
Is it possible to get a pic of the receiver without bold and of the back of the triggerguard?
I just mailed a man who works at a book about trainer for a closer manufacturer mark ID.
What is the bore diameter ??? 6,5 or 7,7 mm.
Best
Well,
heres the ID from the trainer rifle expert:
It’s a so-called Nippon Special Steel T-99 long training rifle. Very common. The pistol grip kanji translates “stopgap” or “substitute.” Let me know if you need more info.
Best Genki