Japanese Fuze ID needed

[RTFREY]

My 1st post. Please excuse any errors.

Can anyone ID this fuze?
thanks,
Bob Frey
Shenandoah Valley of Virginia

SAM_0477.jpg

SAM_0476.jpg

[John D. Bartleson Jr.]

Hope this helps. Drew and Bouganville are our Japanese experts.
John

[BOUGAINVILLE]

A-2(b) ARMY MECHANICAL IMPACT NOSE FUZE

TYPE - ARMY Air force mechanical impact nose fuze with instantaneous action.

BOMBS IN WHICH USED
• 15 Kg Anti-personnel- Army type
• 50 Kg Incendiary (phosphorous rubber pellets)
• 50 Kg Type 92 Gas bomb

COLOUR - Natural BRASS.

OVERALL LENGTH - 2.25 inches (with vanes), (less gaine).

OVERALL WIDTH - 1.67 inches.

MATERIAL OF CONSTRUCTION - Brass except steel spring and steel firing pin.

POSITION & METHOD OF FIXING IN BOMB - The flue is screwed into the nose of the bomb and tightened with a spanner wrench. A grub-screw is usually present in the nose also.

COMPONENTS OF EXPLOSIVE TRAIN - This fuse has an Army gaine with the primer in the gaine. The striker enters the gaine, pierces the primer and sets off the exploder assembly.

FUZES LIKELY TO BE FOUND WITH - Probably none; may be fitted to bomb with an Army tail fuze.

THREADS - 1-5/32 in. diameter 13 TPI

DESCRIPTION (See diagram)
The fuze body (6) is machined out of the one piece. The striker spindle (5) is retained in the body by a shoulder and is restricted to vertical movement only by a stud sliding in a groove in the fuze body. Screwed into its base is a striker needle (7) splayed to a point. The vane boss (vane cap)(1), to which two-bladed vanes (2) are attached, screws on to the end of the spindle and is prevented from being jammed against the fuze body by two studs (3), one on the body and one on the vane cap. The U-shaped transit safety fork (4) is withdrawn on loading into the bomb rack.

A steel creep spring (8) keeps the striker needle off the detonator after the boss has fallen off. A striker guide plug (9) and a detonator (11) screw into the base of the fuze body.

ACTION
On release, the vanes rotate 10 times and the boss falls off. The distance between the striker point and detonator is approx 3 mm which means that the fuze is armed after 5 revolutions of the vanes.

Upon impact with the ground, the arming spindle is pushed in against the action of the spring and the striker pierces the primer which is located in the gaine.

[RTFREY]

Thank you for the information.
Bob Frey

[ogreve]

Hi,

Hmmm, I was asked about this one by e-mail yesterday. From my copy of OpNav 1667 I thought the A-2(d) kind came closest, but the pictures in my copy of it are far from perfect. Can anyone ID it beyond a doubt as either the (b) or the (d) kind?

Cheers,
Olafo

[BOUGAINVILLE]

Olafo is correct, it is definitely A-2(d). In was in a rush this morning with only a few minutes before rushing out the door to work. Now its evening I have more time. Below is the required information on the A-2(d) fuze as well as a few more bits on the A-2(b) fuze for a comparison. The bevel at the bottom of the vanes clearly points to this fuze being A-2(d).

I don't have the splurge on it as I do for the A-2(b) but the attached files tell all. Also try this link to download a PDF file I produced of a Manual on Japanese Bomb Fuzes.

http://www.bocn.co.uk/vbforum/downlo...do=file&id=478

http://www.scribd.com/doc/57872443/T...Japanese-Fuzes

Cheers,
BOUGAINVILLE

[RTFREY]

Thanks to all. This has been helpful.
R Frey