Graybeard Outdoors banner

Confederate pattern 24 PDR Mortar

4K views 23 replies 7 participants last post by  GGaskill 
#1 ·
If you ever get a chance, go to the N-SSA Nationals at Fort Shenandoah in Northern Virginia. Go for the Cannon and Mortar shooting. There is just something about seeing 50-70 Mortars on line, lobbing ball down range. By far the most popular mortar seen in the Confederate Pattern 24 PDR. The reason, it is the simplest and easiest design to duplicate.



Several year back I acquired a piece of steel to build a pop can mortar from. When I went to Fort Shenandoah I wanted a 24 PDR. I looked at the piece of steel I had an decided the best I could do was a 6 PDR. I had the steel bored out to 3.67 inches and a mould made to cast 3.58 inch zinc round ball. The mould is currently lodge with Rotometals.

I picked up the plans for the Confederate Pattern from the West Bros. in Virginia. I scaled them done for my 6 PDR. Here is their barrel plan.



The were some issue with this project and it has been shuffled off to the side a number of times. Issues, being my lack of skills or equipment.

In 2011 Southpaw and L, "banded" the mortar tube and cobbled together a base and made the Junk yard dog just in time for the CBCC I.





This mortar is about as big a mortar that I would want to crew alone. It weighs some where close to 90 lbs and is a handful.

I am have located a lathe that I can use to add the rear radius. Then I can weld on the trunnion and build the carriage. I have the wood-true southern yellow pine and handles. This project will come after I rebuild the Lapan.

I brought this up because Bruce mention the topic over in the bowling ball thread. Hope it gives you some food for thought, Bruce.
 
See less See more
3
#4 ·
Thanks very much for posting it Douglas.

It gives me some stuff to think on. I am hoping a Mortar is going to be my next project after the Hughes Gun is finished. A confederate design surely appeals to me. But like you, I have somewhat limited tools, so when I have to depend on others to do stuff I cannot. Things come to a halt real quick. If I had the Machinery, things would get done much faster.

These projects are very Fun for me. I do not even consider it work..When I get a project done, there is always a feeling of emptiness of some sort. So I have to come up with another quickly.

Some can sit and watch TV or sit in a Bar. Or watch the sunset :) I have to always be doing something I think is useful.. Or I get anxiety trying to figure out something to do.

Are there any pics of originals out there of the Confederate 24 PDR?

I did a short search and never came across any..

Can zinc balls in a Mortar be reused if recovered.
 
#5 ·
I was wondering what the smallest size mortars that are used in competitions? I imagine the NSSA competitions use only authentic calibers/bore size, e.g. large. Are there other competitions where golf ball size mortars are used?
 
#7 ·
Fredstaple said:
I was wondering what the smallest size mortars that are used in competitions? I imagine the NSSA competitions use only authentic calibers/bore size, e.g. large. Are there other competitions where golf ball size mortars are used?
At the last Cut Bank Cannon Convention we had a hole in one contest and every one who was there competed.
 
#9 ·
The N-SSA Nationals in Winchester, Virginny are May 18-22. anyone wanting to attend it's FREE and can give my name Pat Kelly so you are then a guest and not a visitor as there is a difference. Saturday the 21th is the artillery competition. Guessing 50 full size cannon give or take one or two depending on who shows. It is something amazing to watch!
Give me a call at 540-878-8024 if you plan to attend.


www.n-ssa.org
 
#10 ·
Any chance the big guns will shoot on Sunday too? This is an event I have wanted to see, but have a commitment all day Sat. Would be nice to pick up some black powder at the same time.
 
#11 ·
The N-SSA Nationals are a HUGE undertaking and spread over five days of competition to squeeze it all into the program. The Mortar Match is Friday the 20th 4:30-5:30PM.
There are 76 full scale mortars entered for competiton at this point and it includes guns from 12 pounds all the up to EIGHT inch guns! Those are funny to watch!


The artillery Match is on Saturday from 1-5:30PM which 56 full scale guns entered now. This includes Rifle, smoothbore and Howitzer class guns.


And yes Black powder is sold next door to Fort Shenandoah at the best price you'll find anywhere.
 
#12 ·
I am getting ready to tear down the big bowling ball mortar to do the painting. Once everything is painted and the gun reassembled I will have that project completed.

So what's next. I have been researching a couple of unfinished projects in the shop. One is this project.

I need to cut a radius on the end of the tube. I now have a lathe chuck big enough to hold the steel. I only have to do a excel spread sheet to get the numbers to cut the radius on the the end. This can be done.

Something I haven't given much though to is how to cut the concave radius in the trunnion bar.



I can figure the cuts, but this amounts to one big interrupted cut. When I get to that point I will be seeking the wisdom of this board on how to go about this.

Another issue will be the carriage. The standard carriage for the Confederate pattern is a big block of wood. See the picture in the first post. I have have the wood for this as well as mortar handles Dom made me. I just have to find which storage box they are in.

There is another type carriage that I have seen, and that is the ladder or box carriage. We have had discussion and pictures of this style carriage before, but time and software upgrades have lost the pictures. The discussion started with the block versus sled design. The sled of course being from the large seacoast pattern 1840 mortar, having an elevation screw and is not a Coehorn carriage. The discussion eventually lead to the red ladder or box carriage. There was at that time some question as to the authenticity of that style carriage.

https://www.go2gbo.com/forums/88-bl...y/144400-correct-type-bed-coehorn-mortar.html

Last year while in Gettysburg I picked up an Artilleryman Magazine and saw picture of the ladder carriage mortar in an article on the Smithgall Artillery Museum.

Yesterday I started looking for pictures of that gun and carriage. I googled Smithgall Artillery and found the phone number, so I gave them a call. I was hoping they might provide me some pictures or maybe even a drawing.

The phone rang, one ring and voice answered, "Smithgall". Charlies Smithgall himself answered the phone. I ended up having a very pleasant 10 minute conversation with a very nice man. I was so impressed talking to him, so friendly so helpful. Mr. Smithgall is very nice and helpful man. He didn't care I am only making a model, he only cared, I was interested.

As we were talking he sent me via text a picture of the mortar. I don't have permission to share the picture. I was too awestruck talking to the man and forgot to ask. You can see the same picture here in this article from Artilleryman magazine.

https://static1.squarespace.com/sta...ction+-+Summer+2019+Artilleryman+Magazine.pdf

Mr. Smithgall told me how he had found that mortar in a junkyard, one side completely rotted away, but all the hardware except one nut still there. He had Steen rebuild the carriage. Mr Smithgall suggested I contact Steen for drawings. I think I will. Mr. Smithgall said this is an authentic 12 PDR on a ladder frame.

So that is where I am on this project. I need get the bowling ball mortar painted and build a K.I.S.S. the can mortar for a friend first. But this 6-PDR project is looking more and more like a reality. What can happen making that big interrupted 3-inch radii cut in the trunnion? Break tool bits, bounce the lathe across the shop?
 
#17 ·
That Artilleryman magazine article on the Smithgall collection is unbelievable. Mind-boggling unimaginable over the top! That far surpasses every museum in the U.S. with cannons, and probably exceeds the total in all those museums, combined.

Good luck with your project.
 
#20 ·
Apparently fototime is using an obsolete version of https and my browser (Firefox) does not support it as a default. I told Firefox to allow two out of date https protocols and that made the drawing visible. It does display in Edge with the default configuration.


I am guessing that drawing is for the full size piece? You also note, I am sure, that the section shows a second radius perpendicular to the obvious one. I am guessing that radius is the same as the hemispherical end of the tube. Cutting that will be a challenge.
 
#22 ·
So is your size ratio going to be 3.67 (6 pdr bore) to 4.62 (12 pdr)? That is .794 which is not much of a difference. What is the diameter of your tube stock?
 
#24 ·
So now that I see the drawing in post #1, I see you are going with 79% (actually 6.25/7.75=0.806.) It shows a hemispherical bottom with a radius that is half the diameter, so the trunnion radius in the detail should be 3.125, the diameter should be 1.81 and the length should be 12.3.

If you have a 12" face plate for your lathe, you could bolt the trunnion to it, and add a couple of counterweights to balance it, then rough the breech cut in flat, and HNC (human numerical control) the other arc.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top