No, they are actually quite terrible, especially the one shown, which was one of the Navy survey documents done in a rush right after the end of the war. The best US manual on Japanese ordnance was the OPNAV book, mostly because it was all photos. It was made from two earlier MEIU documents that were also very good. Unfortunately the photos and printing of the time limited details in the photos. The wartime OP (which became part of the TM9-1985 series) barely rates a "good", many items are left out, many of the dimensions are wrong and the bomb fuzes are still listed (in the 50s) by the BS US-created designations instead of the actual Japanese designations.
Also very good are the British "Kirkee" documents, which, while only line drawings, are quite accurate. The only drawback to this series is that it is limited to what was found in the Burma region, and has little on what was used elsewhere.