What is this? Vicksburg Tour --- "Vent Holes"

DixieRifles

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After our CWT Vicksburg Tour, I wanted to start a new discussion/research topic. I am NOT an artillery expert but I had to post this Question.

Monument Jeff Davis.JPG


During a stop at the Jefferson Davis Monument, @redbob called us over to some cannons behind the monument. He gave a quick talk about one of the cannon that appears to have repairs to the vent hole. Bob said the original vent hole was plugged and new vent holes were drilled. This gun has 3 holes.

I have talked to a re-enactor who owns an original cannon and my friend who works at the museum at the Gettysburg National Military Park.
Here is a close up of the repaired tube.
Vent Holes.JPG


The Original vent hole has a typical repair. This was performed at arsenals during and after the war when the vents were found to be worn larger than normal due to constant wear. The tube was sent to an arsenal where the old vent was drilled out and typically a copper or copper/bronze insert installed.

However, the 3 holes off to the side were not new vent holes. As we observed in the park, these 3 holes are drilled in a unique triangular pattern and each hole was threaded. These 3 additional holes are typical of a post-war upgrades to add a rear sight fixture. Before the Spanish-American War, the Army was using these old cannons to train artillerymen before advancing to the new breech-loader cannons. There were a handful of examples of these old guns used to train National Guard units during the Span-Am War, after which they were all condemned for further field use.

The Army even modified the Civil War cannons to convert them to breech-loaders. I have found only one example of a muzzle-loader that was actually put into service with the army.
3.2-inch gun M1897

I would like to find a photo of a sight that was bolted down on this gun. Could the same sight have been used on other models of cannon of this period?

What about it, Bob?
 
I am also most definitely not an artillery expert and to be honest, I got to thinking about the vent hole grouping/threaded hole business on the tubes on the way home and realized that I was probably wrong about them being field repairs for a vent hole. Confirmed field repairs for blown vents that I have seen were closer to the original vent hole and definitely not threaded, but I'm not sure about these holes being for another sight; as to sight the piece I would think that the sight would need to line up with the midline of the tube (unless they were like some of the Parrotts) and these would place a sight close to the vent hole. Also, these holes were seen on other bronze Napoleons in the Park and they all had the triangular hole grouping on the rear of the breech for the Pendulum Hausse sight mounting bracket. Things that we know (or are reasonably certain of) are that they aren't vent holes and that they were drilled and threaded on bronze tubes for some reason or another. Now all that we have to find out is for what. My apologies if I led anyone in the group astray as to the purpose of the holes and I'll admit that I was wrong. Also, the only Civil War era gun that I know of that was converted to a breech loader was the 3" Ordnance Rifle and there is at least one still out there as it recently came up for sale.
 
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As far as I'm aware, in Parrotts and Ordnance rifles the vent holes came from the foundry (threaded?) to accept a ready made (and threaded? I'm not sure on this point, I was like 12 when we pulled the plug on my dad's parrott) copper slug with a vent hole through bored through it. This meant that if the vent wore out, you could drill two holes in the top of the plug and use a special wrench to remove it, and insert a new one. I believe when you insert a new plug, you cut away the part of the slug that stuck up above barrel, returning it to a smooth appearance.

Now, I'm not getting this from a manual or anything, this was just information passed on to me from my dad, and I have no idea how correct it is, but I've never seen an original Parrott without a copper vent hole.

That might also be partly to prevent sparks when you are picking the powder bag. Nobody wants to go BOOM!
 
I don't know what artillery the Army used in the Span-Am War. I could almost see them using muzzle loaders but why use that if they had any kind of breech-loader that used metal cartridges. Then again, we know how far behind the Army was at the start of WW1 and WW2. In WW2, the Army drilled with wooden guns and issued old French Petaux 37mm guns until they could build their own 37mm guns.

I was waiting to see if my buddies could find examples of the sight that was used.
 
Those of us who read Horatio Hornblower books in our youth may remember how touch holes were repaired in the field; well at least on British naval guns.
Having not read this fine series of books and only seen the TV series, please share how they did it-inquiring mind(s) want to know.
 

The last cannon in this video has a percussion cap ignition, with the hammer, and the lanyard attached, I wish I could find a better photo of one.
I believe that we may have our answer. I've seen pictures of the percussion cap ignition, but I've never seen how one is mounted on a tube.
 
If I had to guess, I bet this gun had a percussion cap ignition system installed at one point, that's what the holes are for!
Just watched a 10Lb Parrott being fired this way at the NSSA halloween match. The problem with these or friction primers is you are liable to pull the gun slightly off target. Which isnt a big deal duringactual combat where you are using explosive projectiles, but when you are shooting for accuracy during a competition it does.
 
Having not read this fine series of books and only seen the TV series, please share how they did it-inquiring mind(s) want to know.

In one of the books a gun is unbushed--a brass or bronze plug called a bushing holding the vent hole blows out. The gunner takes a new plug and files it to fit the hole, which tapers smaller to the outside surface, like an inverted cone. The gunner runs a line down through the hole and out the muzzle and uses it to pull the new plug up into the hole to check the fit. When he likes the fit he pulls it up tight and taps in from inside with a rammer. After firing a few rounds the new plug is tight and sucure.

That's how I remember it anyway; it's been awhile.
 
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In one of the books a gun is unbushed--a brass or bronze plug called a bushing holding the vent hole blows out. The gunner takes a new plug and files it to fit the hole, which tapers smaller to the outside surface, like an inverted cone. The gunner runs a line down through the hole and out the muzzle and uses it to pull the new plug up into the hole to check the fit. When he likes the fit he pulls it up tight and taps in from inside with a rammer. After firing a few rounds the new plug is tight and sucure.

That's how I remember it anyway; it's been awhile.
That sounds like a plan to me, thanks.
 
I too have my own cannon and I use the Dixie system but I didn't drill on each side to hold it as I wanted to keep it as was. I did have the hole threaded to fit a #10 nipple and I strap the firing mech to the barrel with a narrow belt. The Dixie system was NOT used on any guns but something Dixie came up with. I believe the one above is drilled for some type sight as if for a firing mech there would be holes on each side of the firing hole.
 
After our CWT Vicksburg Tour, I wanted to start a new discussion/research topic. I am NOT an artillery expert but I had to post this Question.

View attachment 331614

During a stop at the Jefferson Davis Monument, @redbob called us over to some cannons behind the monument. He gave a quick talk about one of the cannon that appears to have repairs to the vent hole. Bob said the original vent hole was plugged and new vent holes were drilled. This gun has 3 holes.

I have talked to a re-enactor who owns an original cannon and my friend who works at the museum at the Gettysburg National Military Park.
Here is a close up of the repaired tube.
View attachment 331616

The Original vent hole has a typical repair. This was performed at arsenals during and after the war when the vents were found to be worn larger than normal due to constant wear. The tube was sent to an arsenal where the old vent was drilled out and typically a copper or copper/bronze insert installed.

However, the 3 holes off to the side were not new vent holes. As we observed in the park, these 3 holes are drilled in a unique triangular pattern and each hole was threaded. These 3 additional holes are typical of a post-war upgrades to add a rear sight fixture. Before the Spanish-American War, the Army was using these old cannons to train artillerymen before advancing to the new breech-loader cannons. There were a handful of examples of these old guns used to train National Guard units during the Span-Am War, after which they were all condemned for further field use.

The Army even modified the Civil War cannons to convert them to breech-loaders. I have found only one example of a muzzle-loader that was actually put into service with the army.
3.2-inch gun M1897

I would like to find a photo of a sight that was bolted down on this gun. Could the same sight have been used on other models of cannon of this period?

What about it, Bob?
I am also most definitely not an artillery expert and to be honest, I got to thinking about the vent hole grouping/threaded hole business on the tubes on the way home and realized that I was probably wrong about them being field repairs for a vent hole. Confirmed field repairs for blown vents that I have seen were closer to the original vent hole and definitely not threaded, but I'm not sure about these holes being for another sight; as to sight the piece I would think that the sight would need to line up with the midline of the tube (unless they were like some of the Parrotts) and these would place a sight close to the vent hole. Also, these holes were seen on other bronze Napoleons in the Park and they all had the triangular hole grouping on the rear of the breech for the Pendulum Hausse sight mounting bracket. Things that we know (or are reasonably certain of) are that they aren't vent holes and that they were drilled and threaded on bronze tubes for some reason or another. Now all that we have to find out is for what. My apologies if I led anyone in the group astray as to the purpose of the holes and I'll admit that I was wrong. Also, the only Civil War era gun that I know of that was converted to a breech loader was the 3" Ordnance Rifle and there is at least one still out there as it recently came up for sale.

I’m not an expert either but this was a very interesting discussion about these vents holes! Have learned something new!
 
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