Mortar accidents

[Artilleryman]

Has anyone seen or heard about any mortar accidents where the person doing the loading was injured by a premature ignition of the piece?

[Cannoneer]

I'm not aware of any documented instances of premature ignitions occurring in muzzleloading era mortars in either a historical, or contemporary context.

[oltom]

none i have ever heard of.........but then, downrange is ANOTHER story!

[KABAR2]

I think accidents with mortars is less of an issue due the length of tube and powder chamber
there are less chances for embers to be left behind between loadings and it is easier to inspect
a chamber in a mortar for such than a cannon or howitzer.

[DaveSB]

I spent some time searching for it this morning, but couldn't find it. I swear I came across a video on youtube of a guy in period attire, leaning over a large mortar tube and the powder igniting. The It was like a 20 second video and it was filmed from a distance.
 
Found this: http://artillerymanmagazine.com/accidents.html

[Cat Whisperer]

I have not heard of any accidents, but I have, after 5 minutes, seen a glowing ember in the powder chamber!
(4.5" bore)

 

[seacoastartillery]

     

I spent some time searching for it this morning, but couldn't find it. I swear I came across a video on youtube of a guy in period attire, leaning over a large mortar tube and the powder igniting. The It was like a 20 second video and it was filmed from a distance.
 
Found this: http://artillerymanmagazine.com/accidents.html

     Thanks for posting this list from the Artilleryman Magazine, Dave.  It should be posted at least once per year to show the new people to this hobby that these are no toys we are dealing with here.

     The only one I spotted dealing directly with 'Mortars' actually was not a mortar after all.  I believe I recall this correctly, that Mr. Cook's accident involved the lighting of a fuse to a "Thunder Mug".

1990 Premature Ignition. Meriden, Conn. Larry Cook, maker of cannons and mortars, was injured when mortar went off as he had his head over the barrel.

     As most of us know there are very few ways to safely fire a Thunder Mug.  Because of the position of these devices, being placed on the ground, their muzzles are always lower than most of the firer's body.  Related to any other form of artillery, when you fire a Thunder Mug, you are standing or kneeling in front of the "Plane of the Muzzle" and are subject to concussion and flying debris if a quick or premature discharge takes place.  The safest way to discharge one of these devices is to light a long fuse, one foot or longer with a long linstock while kneeling down as low as you can.  Also position the vent 90 degrees to a line between it and you!  The problem with being close when lighting these fuzed devices is that a premature is far more likely than with conventional artillery, because of the vent's attitude, that of being horizontal where powder can dribble out around the spot where the vent enters the Thunder Mug.  Sparks from the fuze ignition can and do light this loose powder at the vent and Premature Discharge is the result!!  Dire consequences can occur.  BEWARE.

Tracy and Mike

[Double D]

We have almost since the board was started had a  catalog of cannon accidents. There is a link in the reference stickies to these accidents...within the post is additional link to other accidents. 

Cannon Accidents!!! Safety Warning!!!

Here is the interior link.  List of past cannon accidents

The link Dave SB posted is a newer version of that second link and I will add that to the main post...thanks Dave for posting.

Reference the thunder mug.  There is one simple thing that can be done to focus the muzzle blast away from the shooter that I learned from my days of building muzzle brakes for a world famous muzzle brake company.  Make an angled "crown" on the muzzle- simply  touch of a tool in the lathe at the standard 30 degrees on the muzzle and make a flat no more the 1/4 inch and as little as 1/8 inch.  Then when the gasses initially escape at the muzzle, the gases will be directed at angle up instead of straight 90 degrees when they exit the muzzle.   The German documents that the company had where I worked  studied the gas redirection at length for use in heavy mobile artillery pieces to reduce the effect of recoil on the vehicle. They also study gas redirection to reduce dust signature, and damage to adjacent equipment and men. This angle was was all that was needed to deal with that problem.


As to fuse, to long a fuse can be just as dangerous as to short a fuse.  Definitely use fuse to light the mug.  Know your fuse burn rate.  Use enough fuse to allow you to get well away  from the mug, say 15 seconds.  Gone are my days when I could do the 100 yard dash in 9.5 seconds---okay okay, 10.5 maybe...But a I'll bet I can get 100 yards away in 15 seconds. 

As to powder out the vent.  If you are using the right size of powder, this shouldn't be an issue...but human nature such as it is....when you cut your fuse, like Tracy says consider the possibility the powder might run back out the vent.  This seems the perfect place for a fused quill.  Make quill with a 15 second fuse attached. If not for your fuse, time it from the vent to ignition point.  You should also know how long it take to burn from vent to powder.

As Tracy stated, watch which direction the vent is pointing.. point it down range. 

Also watch the wind direction you do not want to discharge this thing up wind and have burning debris raining done on the the spectators.

We can minimize the the chance of accidents by following safe procedures and to do that we just have to think first.

[DaveSB]

your welcome gents, the sad part is nearly all (if not all) of them could have been prevented with knowledge.

[oltom]

Premature Ignition.....seems to be THE most accident listed~

and if folks would use a 'safety' rammer, and follows proper powder charge storage rules.....most of these would of never happened~

[gunsonwheels]

Good dialogue... there aren't that many safety rules but I have noticed from my own review of a few accidents that it seems more than one "DO NOT CROSS" boundary was crossed when the accident occurred... for instance... inadequate swabbing and crossing the line of the bore with body parts usually go together.  I think it is easy to be safe but you cannot stop thinking about it for one moment or it will rise up and bite you.  I remember the guy who lost an eye, hand and forearm from not sufficiently wet swabbing and combined that with ramming home the powder without a safety rammer saying, "it was my own darn fault, I knew better but didn't follow the rules".
 
For the safe shooters the biggest part of the problem today is there are media types and politicians out there just waiting for a screw-up to occur so thay can try to take away our equipment, supplies and liberties to shoot...  BE SAFE (for you and others) and at the same time DON'T GIVE THE IDIOTS ANY IDEAS OR EXCUSES TO TRY TO CANCEL OUR SPORT.   ...please... 

[Cannoneer]

Absolutely, DaveSB! Reply #8

I'm with you, kaintuck; a safety rammer used for loading the long tubes, would go a long way in preventing any serious injuries form occurring due to premature ignition. Reply #9





Edit 9/3/11: For content. I got post attributions mixed up.

[Artilleryman]

My original question had to do with mortars, and the comments have moved to artillery pieces which is of course a beast of a different color. 

My next question is: Is it necessary to devise additional safety procedures that go beyond the original drill for mortars given that there doesn't seem to be any accidents with premature discharge of a mortar?  If so what should those procedures be?

[Double D]

Sorry, Norm we drifted...this group is so easily lead astray..

[Artilleryman]

Sorry, Norm we drifted...this group is so easily lead astray..

No problem.  Safety discussions can be very interesting. 

[GGaskill]

If so what should those procedures be?

Seems like premature ignition is less of a hazard with a mortar since you can inspect the bore better and you don't have to ram the shot.  Burns would likely be the main hazard from a premie as long as you don't stand in front of the muzzle.

I think another potential source of premies would be the shot crushing a powder grain when it hits the bottom of the bore.  Supposedly modern BP cannot be ignited by percussion but a procedure that limits the landing velocity of the shot couldn't hurt.  With bowling balls, the web between the finger holes could be drilled for a piece of nylon rope so you could lower the ball without sticking your arm down the bore.  For non-ferrous shot, you wouldn't be able to hold them magnetically so maybe intersecting holes and a length of strong fishing line would do the same thing.  For ferrous shot, a magnet on a stick would work but it would need something to push the shot away from the magnet at the bottom.

[gunsonwheels]

My next question is: Is it necessary to devise additional safety procedures that go beyond the original drill for mortars given that there doesn't seem to be any accidents with premature discharge of a mortar?  If so what should those procedures be?

With mortars there are a few different if not additional sources for safe firing consideration:
 
The body parts hovering near the front of the muzzle requires greater care to be safely managed.
 
The fuse-hole/vent exit trajectory is also harder to safely manage.  Blast out of that hole has burned or otherwise injured more than one person with mortars.  Cannons blast pretty much straight up.
 
When considering the zones of most (or least) fragmentation of an exploding cylinder..., there are safer (or less safe) places to be (or stand) when the charge goes off.  I have found it is somewhat harder to identify those zones and even harder to try and be in the safer area when things go bang with mortars than with cannons.
 
On the up-side... it is easier to see if your swabbing did its job. 

[Cannoneer]

Artilleryman,
Do you have any photos of the loading of your siege mortar? Weren't two men used when loading with the original shell tongs, one to each side, so nobody had to stand in front of the bore?

Cannoneer, You are partially correct.  I have summarized the following information from the  manual "Instructions for Heavy Artillery".   On a 10 inch siege mortar a handspike is passed through the ring of the shell hooks and lifted for wiping and then lifted and lowered into the bore with the gunner in front who helps lower the shell gently into the bore.  This is basically the same procedure used for the 10 and 13 inch seacoast mortars.

On an 8 inch siege mortar the gunner stands in front of the mortar and with shell hooks lifts the shell to be wiped and then lifts and lowers the shell into the bore.  I preferred to stand as much to one side as I can to lower the shell into the bore.  Since the shell weighs 45 lbs that is not easy to do.

As hazardous as this sounds, what would cause the mortar to fire prematurely?  You can see the entire bore during cleaning.  Since no cartridge bags are used unless you have a sub chamber, there are no bag fragments to hold an ember.  Even if there were you could see it and deal with it.  For arguments sake lets say that you left an ember in the bore.  That would set off the loose powder when you poured it into the barrel well before you would load the shell.  I would be more worried about that than loading the shell.

Artilleryman,
I found the exact images that I was thinking of, it's a cannonmn YT video of the fall 2007 mortar match held at Ft. Shenandoah, VA, and it starts at 1:03 into the vid. I like the way that they shake the pole to break the tongs free, so as to try and not place their hands over the bore.
Everything that you said (that I highlighted in red) makes perfect sense to me, no disagreements here, but I still admire your efforts to try and stand to one side as much as possible when loading your 8-inch.

[Double D]

The reason they are using tongs  and two people to load that 8 inch round ball is because is because it weighs 45 pounds and to just drop it down the bore would bounce the mortar and they would have re register-aim it.

As far a vent debris flying out of the mortar on firing, at the N-SSA events mortars are required to have a vent shield.



I an thinking about requiring them at future Montana shots.

[gunsonwheels]

The reason they are using tongs  and two people to load that 8 inch round ball is because is because it weighs 45 pounds and to just drop it down the bore would bounce the mortar and they would have re register-aim it.

If the windage is tight enough, the air cushion will prevent this... 

[Double D]

It wouldn't be very smart to have that tight of windage in a gun that big.  Beside a ball that tight probably wouldn't pass ring gauging.

[Cannoneer]

"On an 8 inch siege mortar the gunner stands in front of the mortar and with shell hooks lifts the shell to be wiped and then lifts and lowers the shell into the bore.  I preferred to stand as much to one side as I can to lower the shell into the bore.  Since the shell weighs 45 lbs that is not easy to do."

Norm,
Do you and other skirmishers load projectiles in the 8-inch mortars single handedly, because that's the documented and historically accurate way of doing it? In other words; do you load the 'shot' in your 8-inch siege mortar by yourself, in order to remain faithful to the drill that Civil War artillerymen followed?

[Victor3]

Reference the thunder mug.  There is one simple thing that can be done to focus the muzzle blast away from the shooter that I learned from my days of building muzzle brakes for a world famous muzzle brake company.  Make an angled "crown" on the muzzle- simply  touch of a tool in the lathe at the standard 30 degrees on the muzzle and make a flat no more the 1/4 inch and as little as 1/8 inch.  Then when the gasses initially escape at the muzzle, the gases will be directed at angle up instead of straight 90 degrees when they exit the muzzle.   The German documents that the company had where I worked  studied the gas redirection at length for use in heavy mobile artillery pieces to reduce the effect of recoil on the vehicle. They also study gas redirection to reduce dust signature, and damage to adjacent equipment and men. This angle was was all that was needed to deal with that problem.

 I doubt that this angle would be all that helpful on a thunder mug.
 
 With a projectile, yes. Gases are initially released at high velocity between the base of the projectile and muzzle face as the projectile exits. Directing gases forward/upward via a concave cone has its benefits here.
 
 With a blank, not so much...

[Artilleryman]

"On an 8 inch siege mortar the gunner stands in front of the mortar and with shell hooks lifts the shell to be wiped and then lifts and lowers the shell into the bore.  I preferred to stand as much to one side as I can to lower the shell into the bore.  Since the shell weighs 45 lbs that is not easy to do."

Norm,
Do you and other skirmishers load projectiles in the 8-inch mortars single handedly, because that's the documented and historically accurate way of doing it? In other words; do you load the 'shot' in your 8-inch siege mortar by yourself, in order to remain faithful to the drill that Civil War artillerymen followed?

I cannot speak for the crews of other eight inch siege mortars.  Some, as shown in the video you posted use two men, our crew uses one.  This is the way we were taught by the Paulsons.  An interesting note is that it takes five men to load a 13 inch mortar shell, one who stands in front of the muzzle.

One of the things that we do besides cleaning the bore carefully between shots is that we do not introduce powder or load shell if there is an adjacent mortar that is going to fire.

[Double D]

Reference the thunder mug.  There is one simple thing that can be done to focus the muzzle blast away from the shooter that I learned from my days of building muzzle brakes for a world famous muzzle brake company.  Make an angled "crown" on the muzzle- simply  touch of a tool in the lathe at the standard 30 degrees on the muzzle and make a flat no more the 1/4 inch and as little as 1/8 inch.  Then when the gasses initially escape at the muzzle, the gases will be directed at angle up instead of straight 90 degrees when they exit the muzzle.   The German documents that the company had where I worked  studied the gas redirection at length for use in heavy mobile artillery pieces to reduce the effect of recoil on the vehicle. They also study gas redirection to reduce dust signature, and damage to adjacent equipment and men. This angle was was all that was needed to deal with that problem.

 I doubt that this angle would be all that helpful on a thunder mug.
 
 With a projectile, yes. Gases are initially released at high velocity between the base of the projectile and muzzle face as the projectile exits. Directing gases forward/upward via a concave cone has its benefits here.
 
 With a blank, not so much...

Doubt it all you want, but it still works. The gases are still expanding and still moving at velocity even in a blank.  Try it and see.

[Victor3]

 I'm open to learning DD, but we all sometimes fall into the error detailed in my sig line. If you have relevant data to back your theory concerning thunder mugs, blanks, etc., please share it; It's helpful for us gun guys to learn new (to some of us) things about fluid dynamics related to ballistics, etc.

[Cannoneer]

As far a vent debris flying out of the mortar on firing, at the N-SSA events mortars are required to have a vent shield.

I an thinking about requiring them at future Montana shots.

I believe that these skirmish assoc. rules came into being because they use friction primers to ignite their mortar charges, and the spent tubes are blown out with considerable force. Were there any issues at the 'MT Shoot', with debris blowing back out the vents of the mortars?

[Double D]

Its not just friction primers that blow out of the vent, but quill straws and hot fuse ash are all expelled as well.  I have in the past been hit by the debris flying out of the vent from both type of ignoition devices.  Walk around behind a mortar after a shoot an you will see the debris laying all over the ground.   I do believe Southpaw got hit in the arm by flying debris at the Montana shot if not he did at the 4th of July shoot. He uses nothing but quill and fuse.

[gunsonwheels]

I appreciated the pic of the mortar vent shield.  Had a family of boys over the other day and shot a golf ball for them... for their safety and because I shoot out the side from a covered carport , I didn't want hot fuse debris coming back, put a piece of 2x4 leaning from the edge of the muzzle down to the floor.  I think I have a piece of 8x8x1/4" angle out there someplace so will set out to find it and trim it up to look like the pic... thanks for posting the pic... some of us are kinda new to the mortar thing... now if that GBOBPM&C cast insignia was only available... 

[Double D]

I'm open to learning DD, but we all sometimes fall into the error detailed in my sig line. If you have relevant data to back your theory concerning thunder mugs, blanks, etc., please share it; It's helpful for us gun guys to learn new (to some of us) things about fluid dynamics related to ballistics, etc.

Setting aside the insult implied by your reference to your signature line, I can only share what I was taught in college about the effects of crown and crowning, and later seeing the results of of those teaching testing muzzlebrakes.   Sorry can't give you a scholarly work there, just first hand observation based previous education.

If you have something that contradicts these teachings and observations please share it,  not the insults