U.S. 37MM M55A1 round, with M50B2 dummy fuze

Manufactured by WMCo…2-4-43 is that the manufacturer?
Does the color represent anything? USN?
Was this an A/A/A round, or an A/C gun round?

Andy–The blue color denotes a Target Practice (TP) round.

BTW, I fixed up your links so they would show up in your post. In the future, choose the “img” (the bottom choice), not the “http” link.


Thankyou Mr Ron.
Would that have been fired into a soft target, and survived, never fired, and from an Airacobra, or from the ground?

WM Co.?

Andy–Your round has never been fired as evidenced by no rifling marks on the copper driving bands.

I do not know who WM Co is.

OK Ron, I thought the bands lost their color from being fired,thanks

Andy–To my knowledge the driving bands on all projectiles of all sizes are never painted. I think it might have to do with the paint would foul the rifling if the bands were painted.

Thankyou Ron…perhaps someone will know the maker, and the type of 37MM weapon it was designed for…

This M55A1 projectile is a TP-T (Target Practice Tracer) and it was loaded in the 37 mm Mk. IIIA2/IIIA2B1 case (37 x 145 R) for AN-M4 and M10 aircraft guns, and the 37 mm M17/M17B1 case (37 x 223 SR) for M1 (AA) and AN-M9 (aircraft) guns. It was made by Westfield Manufacturing Co. of Westfield, Massachusetts.

Here is 37 mm for M1A2 & AN-M9 with a TP-T M55A1 projectile with M50 dummy fuze made of plastic:

Would the Airacobras cannons accept this projectile? Was it made for us with the P39 variants?

Yes, it will! Just keep in mind that the AN-M4 and M10 guns had 145mm cases.

Anybody have an extra 145mm casing F/S?

This is the 15-round articulated link belt and feed box for the M4 cannon: