I scrounged the net for info on this matter of the IJA using these things and could find no conclusive evidence to support the statement of the crossfire claim with wooden bullets.
If you have a blue on blue in an ambush well that's just tough should have planned your fields of fire a bit better but the Japs killing themselves I do not think the GI's would have minded one iota.
The forum knows I horde books, my passion is Aust WWI first Ed's in H/C whilst a slow and expensive passtime I assure you the ones that are written in the first person by the ones that were there are not embellished with the journo's wild imagination on how it was, they are graphic in detail of what happened to them and all their trials and camaraderie which I feel makes the complete picture.
I have a S/C called "Strike From The Sky" about their bombing of the factories in WWII Britain by the Luftwaffe and it is rather a surprising book as it is as close to the real thing graphically in words that you can get of women factory workers and men who met their demise at the end of a bomb blast.
I read because I want to try and understand what the people of those generations went through as my father never spoke of his WWII 4 years overseas on land and I am not a blood and guts person either I saw enough blood gushing out of cows necks & handling nice & hot cow hearts when I worked on the slaughter floor of an abattoir then in their offal room.