Maybe something like the Otsu with a 10-round capacity or in other words, a Japanese version of the ZH-29. There were also other rifles derived from it, like the Z-37, though that one would be more likely to appear with the Germans.
I’m not entirely surprised that this has ended up as a BP weapon for Japan, and personally from everything I’ve seen here on the forum and thanks to the assistance of others, their hard work and my own research I frankly prefer this as a BP weapon.
Personally as it stands I think the most suitable choice would be the weapon suggested by @Valkay and their topic on the Shenyang Arsenal ZH rifle with a 20 round magazine.
It can’t be BR3. The ZH-29 with a 10 round mag is BR4. It would have to have genuinely horrid stats on a level that it won’t be used to be at BR3 and that’s just a waste of a BP.
Jus like the us
A 20 round sa rifle could be usable if and only if it’s uses stripper clips or by magic is as slow as if it used them, two things the zh32 never would be