U.S. Navy Designation Help


#1

For Ray Meketa. Ray, I recently acquired a 5in-51 Catapult shell which is so marked. The mouth is perfectly round, but measures exactly 6 3/8 inches inside diameter. Is there any relationship between the 5 inch designation and the fact that the shell ID is 6 3/8 inches ??? Do all USN shells have such a wide discrepancy ??? Thanks, Bill Ballard


#2

Bill

Catapault cartridges were waaay before my time so this is all conjecture and WAG on my part.

The 5"/51 was a bag gun, except for a few at the end of it’s life that were seperate loading. I think the seperate cases may have been bottlenecked. If so, a catapault cartridge made from a 5"/51 case would have been cut off and the mouth would have been considerably larger than 5".

How is yours marked? Is it stenciled or stamped? A few measurements would tell a lot. How long is it. What is the rim diameter. Things like that.

Sorry I can’t help more.

Ray


#3

A couple of links to expalin its use. And being a cutdown tapered shell would effect “bore” dia., hence the 6"+ reading.

navsource.org/archives/01/057/015701l.jpg

acc.kitreview.com/p6catapultreviewpb_1.htm

flightglobal.com/pdfarchive/ … 01162.html


#4

Great info, Rick! That has to be one of the larger "CAD"s used for sure…Would guess there’s not too many of those cases kicking around anymore.

Here’s a pic of the USS Mississippi where you can see the catapults.
en.wikipedia.org/wiki/File:USSMi … iBB-41.jpg

Dave


#5

Ray, the case is 33 inches long and is straight. The rim is 7 1/4 inches in diameter and 9/16 in. thick with about a 3/8 inch wide bevel. The case is stenciled on the side “CATAPULT AMMUNITION”, “PRIMER MK14-1TS-39 IGN CHG 300 GRAMS”, “BLACK CANNON POWDER CHG 21.75 LBS. S.P.D. 3595”, “BEFORE LOADING IN GUN REMOVE MOUTH PLUG CARDBOARD DISTANCE PIECE & WOOD DISC”. The head is stamped " 5-IN-51 CAL MK-3 CATAPULT NS- 1942 J.C.A. LOT 58". I don’t have a scale big enough to weigh it, but I would guess about 25 pounds. Hope this helps. By the way if someone could tell me where to find a photo of a true 5-in-51 shell case, I would appreciate it. Thanks, Bill


#6

Thanks, Rick. They are good links. I am in the same category as Ray – waaay before my time. Bill


#7

Ballard,

That’s a big one at 33" long! I had pictured in my mind (for no good reason) something about half that length. I would think that would win most bets you get into for “Largest CAD Cartridge” competitions! 21.75 lbs. of chunky black powder burned off at relatively low pressure must’ve been a real treat to clean up after! Great item and thanks for the detailed info on the markings.

Dave


#8

Bill

That’s a new one for me. I agree with Dave - the mother of all Impulse Cartridges! It looks like you found yourself something special.

I don’t think I’ve ever seen one of the 5"/51 seperate loading cases. Some of our Big Ordnance guys must know what they look like.

Ray


#9

Some tidbits.

First, the 5" 51. Still haven’t located pics.

hnsa.org/doc/ordnance/pg078.htm

The specs match yours, mostly.

And this, about when they started using this system.
From the NY Times, Oct. 17, 1921.

query.nytimes.com/mem/archive-fr … 838A639EDE

All this might help narrow the search criteria for those that are interested.


#10

Thanks to everyone. I now know more than I thought I would ever find out. Regards, Bill


#11

Bill,

Your case dimensions are correct. This is not a cut down.
A few years ago I saw a headstamp pict wich I show.
Could you please post some pictures of your case?

Thanks in advance,
Rien




#12

Western, I do have photographs, but do not know how to use Photobucket yet. If some kind person will send me an email to wd.ballard@pvco.net I will send them to them for posting. Thanks. Bill


#13

Bill , thank you so much for sharing your pictures!
This is a rare case and the ink stamps makes it a very nice piece.


#14

Thank you Rein for posting the pictures. Some day I may have time to learn how to do it myself. Regards, Bill


#15

Bill,

That’s a great case and I would dare say a very desirable one at that! Thank you for sharing the info and images.

Dave