12 inch Coast Defence Mortar

Greetings Everyone, could anyone please supply me with or point me in the right direction for info on 12 inch Coast Defence Mortar ammunition as used in this ordnance in the Phillipines during WWII? Does anyone know how these projectiles got to be in Australia?
Thanks, Peter.

Hi Peter,

Can you provide a photo of the projectiles in question? I can likely ID them for you and provide a reference.


Howdy Jim,

Thanks for the reply, I don’t know how to put a pic in this forum, but I can send you one if I have your E address, mine is ozziammo@chariot.net.au.

I remember you helping me out a couple of yrs ago on some Nordenfeldt case IDs. but have had a hard drive crash since then & lost my address book.

Regards Pete.

FYI, their are detailed instructions on how to post pictures here located on the top few topics on the main index. It helped me and made it easy. Sounds like a cool projectile.


I don

4 sure! I’d love to those pics :-) Thanks so much.

Here are some photos of the 12

Totaly AWESOME! thanks Phil!


Peter asked me to post this great photo of the shell in Austrailia on his behalf.


Thank you Jason for posting the pic, thanks also to Phil for the great pics of the Ordnance, all great info for the perpetuation of history.
Regards Peter.

my pleasure Peter! Thank you and Phil for providing the great pics here. Super interesting stuff

Anyone know if these are the same type of 12 inch mortars that were installed at the San Francisco Presidio? Have been to the Presidio but there is nothing but the pits left. There is a 12 inch disapearing gun still there.

The book “Artillery at the Golden Gate,” by Brian B. Chin, shows a very small picture of a 12-inch mortar on page 15, with the caption “12-inch seacoast mortar of Battery Howe at Fort Funston as fired by ROTC Cadets on July 12, 1938.” Fort Funston was at the South end of the coast of the City and County of San Francisco, near what is today Daly City. For those not familiar with the city, the borders of the City and of the County of San Francisco are identical, one of the few such counties in the entire United States.

The gun appears, although it is hard to tell, to be the same as the one pictured on this thread. It is the only picture of such a gun in the book, although there is mention of these mortars, as well as 12-inch rifles and many other types of gun up to and including a couple of 16 inchers, being spread around the coast and the opening to San Francisco Bay, on both ends of where the Golden Gate Bridge is. Some of the batteries evidently had up to sixteen of these mortars, such as Battery Springer-Livingston at Fort Miley, at the north-west end of the Golden Gate (the entrance to the Bay on the westward side of the Golden Gate Bridge) not far before the peninsula’s coast line makes a 90 degree turn to the south. For those familiar with San Francisco, Fort MIley was near where the current Palace of the Legion of Honor Museum, and the U.S.S. San Francisco monument are.

All in all, it seems that the artillery massed along the coasts of the Golden Gate, the Coast of San Francisco and San Mateo Counties, and in the Headlands of Marin County north of the Golden Gate, were quite formidable.

There are many remnants here and there of the defenses, although few major ones still exist today, and as many know, the Presidio of San Francisco today is no longer a military installation, but rather part of the National Park System. As far as I know, only one gun, the one mentioned by Gamgjm, still remains on display, I believe at the area known as Baker’s Beach. I, personally, have not seen it (although I drove through that area of the Presidio just today with friends) but I know that it is on display at one of the old batteries.

Hi Pete,I think the shell on the picture that Jason posted is a target practice.

There is now a sign at the site of the 12-inch mortars that gives some interesting information, most of which I wasn

Just a bit of added info to John Moss’s data on the motars at Ft. Funston, in San Franciso. At Ft. Point, the Civil War era brick fort, which is located under the Golden Gate Bridge, there is a series of photos showing a Ft. Funston motar being fired.

There about 5 or 6 photos, showing first just a smoke ring as the motar is fired, then the nose of shell first appearing, then continueing until you see the full shell in flight.

Also on display is a group of photos showing the 16" gun barrels being dragged up the cliffs at Ft.'s Barry and Cronkite on the Marin County coast,
after being landed on the beach from barges.

Frank - is Ft. Point open again? It has been closed for over a year. I seem to recall those pictures. I forget, was there a 12 inch mortar among the guns in the court-yard of Fort Point, or around the edges under the parapet?

I think it is probably too big to have put one on display other than in the center of the court.

John moss

Guys, thanks to all of you for great information, it will be beneficial for when I restore & display this item.
Thanks to John Moss for jogging my memory to the fact that he took my wife & I to the Presidio in 1991 for a look at the fort, I will go back through the pics & video to see if I recorded any of that extra important stuff!
A great website, keep it up.
Regards Peter.

John, I’m sure that Ft.Point will remain closed until all of the retro fit is complete on the GG Bridge. There is just to much danger from falling material to allow the public in the area. As a case in point, about 20 yrs ago
some fool dropped a bowling ball from the bridge that landed inside the fort. The darn thing shattered on impact and one of the docents was hit by flying fragments.

Hi Western (and Peter),

Although I can’t be certain without a close-up of the piercing cap and the base of the projectile, I feel that this is the Deck Piercing, M1898. The TP projectile has a deep groove in the cap at about mid-point, whereas the DP projectile does not. This one also lacks the modified (M1907 type) point to the cap, being completely flat instead of slightly pointed, making it a very early (pre-1907) projectile. I could be wrong about this, but based on the single photo, this is my feeling.