Author Topic: Anyone made a 10 inch mortar lately?  (Read 4117 times)

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Offline gulfcoastblackpowder

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Re: Anyone made a 10 inch mortar lately?
« Reply #60 on: August 27, 2010, 06:06:55 PM »
That's really COOL!!!  As in Freezing COOL!!!  8)

What was being fired in that thing?  Maybe that's why it didn't last through spring?  You know fire doesn't mix well with ice/snow for very long, right?  ;D

Offline entsminger

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Re: Anyone made a 10 inch mortar lately?
« Reply #61 on: August 30, 2010, 03:07:04 AM »








The question is what is going to satisfy you.  We can design something that will hoist 220 lb cast iron shot to 4500 yards using 20 lbs of Cannnon grade powder.  It will weigh on the order of 8 tons and cost about 8 tons also.

You have to give us the guidelines.

 ===Scott==
 That makes sense! First to answer one question , I have looked at Herns mortar and the 8 incher really doesn't do anything for me. I even talked to them about making a 10 incher and they said they could for around $1000-1500 dollars. I just don't think the 10 incher would satisfy me, I'd still want a 13 eventually so why spend anything on a 10? Unfortunately I'm just hooked on the 13 whether if can shoot or not. If it can shoot that would be cool, if not that's ok too.
  So what would satisfy me? Well maybe someone could give me a few options of liner/barrel thicknesses and actual ball park costs to shoot varied weight balls and I might get an idea if this is even worth doing at all. Someone mentioned a barrel that would shoot an aluminum ball with one pound of powder. What thickness of barrel might that be and what might that cost me? Say I went up to a barrel that would throw a zinc ball a couple hundred yards, how thick or strong would that barrel need to be and what might it cost? I think the barrel that would shoot an aluminum ball with one pound of powder might do the trick but I don't have a clue what that would be or what it would cost or where I would get such a liner/barrel? Cut a barrel down off a battle ship and put it in my mortar tank, ha ha..
  Thanks for being patient with me guys!!

Offline Zulu

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Re: Anyone made a 10 inch mortar lately?
« Reply #62 on: August 30, 2010, 04:02:19 AM »
entsminger,
Make a full scale mortar out of wood and put it in your living room. :o
Zulu


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Offline Double D

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Re: Anyone made a 10 inch mortar lately?
« Reply #63 on: August 30, 2010, 04:09:05 AM »
You will find all the barrel thickness information in the N-SSA skirmish association rules on cannon construction.  Do you have a set of plans from AOP for the dictator?

When you talked to Paulsen's did you asked about crewing for them once or twice.  

If you really want to do this, I think you need to get on on one of the N-SSA mortar teams.  Shoot with those guys, get some experience.  You will learn how a mortar operates and a lot of your questions will be answered. You will also make contacts withfolks who may share your dream and maybe, just maybe you can do this thing.

Offline entsminger

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Re: Anyone made a 10 inch mortar lately?
« Reply #64 on: August 30, 2010, 05:14:59 AM »

You will find all the barrel thickness information in the N-SSA skirmish association rules on cannon construction.  Do you have a set of plans from AOP for the dictator?

When you talked to Paulsen's did you asked about crewing for them once or twice. 

If you really want to do this, I think you need to get on on one of the N-SSA mortar teams.  Shoot with those guys, get some experience.  You will learn how a mortar operates and a lot of your questions will be answered. You will also make contacts withfolks who may share your dream and maybe, just maybe you can do this thing.


  Yes but I don't think it has costs and such does it? Paulsons Live in Wisconsin and I live in Virginia. I can't afford to go there to crew and they are very particular about who crews for them anyway. I've been to several mortar shoots here and I learn very little there about how to make mine shootable. I just need some general cost quotes so I can figure out if making mine shootable is feasible or not. Most likely not. I'm terrible at these artillery books. I got a few a year or so ago and they are above my head with all the calliber talk and lingo I don't understand. I do have the plans for a 13 inch mortar and I have made a small wood mortar just like the ones pictured. I'll take a picture of it. Just for instance what would a 13 inch liner cost that would make mine able to shoot a aluminum ball with one pound of powder? It doesn't have to be an exact cost, just give me a ball park figure.

Offline gulfcoastblackpowder

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Re: Anyone made a 10 inch mortar lately?
« Reply #65 on: August 30, 2010, 01:04:29 PM »
Compared to the cost of even a nonshooting model, the cost of taking a trip to shoot one would be relatively small, and would have plenty of rewards.  While they may be particular about who crews their guns, most people in this hobby are happy to train willing bodies, so you may be able to persuade them to train you, especially if you express your intent to obtain one for yourself.  At an event where I'm shooting, I'll gladly teach people to shoot all day rather than shooting anything myself, provided there's an interest.

When you say you've gone to several mortar shoots, did you participate or just observe?  Getting hands on will allow you to be much better acquainted with a gun than watching ever will, allowing you to know the right questions to ask so you can learn.  Also, getting experience shooting smaller cannon/mortars can be used as a stepping stone to the big stuff.

Offline Double D

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Re: Anyone made a 10 inch mortar lately?
« Reply #66 on: August 30, 2010, 01:35:38 PM »
GCP, has it right, get to be part a of a small mortar crew.  don't be a spectator.  Be willing to learn  how to shoot the small mortar and everything else involved with it.  Get the experience and network with other Mortar shooters.  Once they get to know you and see you have a genuine honest interest, they will open doors for you.  If some one needs a fill mortarman jump in.  Once you get known, talk with the folks with different mortar, ask if you can crew with them.

The word will get around that you are a serious person and willing to work and increase your chance to shoot the big one.

Offline dan610324

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Re: Anyone made a 10 inch mortar lately?
« Reply #67 on: August 30, 2010, 01:37:08 PM »
you got to understand that its almost impossible to help you to estimate the building costs .

how much can you do by yourself ??
what equipment do you have ??
will you buy new steel or from a scrap yard ??
should you have it in the same style as any existing mortar or will it be enough if it can fire your 10" aluminum ball ??

there is a million variables to think of

start checking the cost for a piece of 13" diameter steel thats 35" long and you will be a little closer than you are now to estimate the cost for your build
Dan Pettersson
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interested in early bronze guns

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Offline GGaskill

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Re: Anyone made a 10 inch mortar lately?
« Reply #68 on: August 30, 2010, 02:41:52 PM »
Like Dan says, the real question is how much can you do?  Once you have to start paying someone else, the cost goes up rapidly.

I think it would take about 500 lbs of steel to make your tank shoot aluminum balls.  But let's think about the cost of shooting it.  A solid 12.9" aluminum ball would weigh around 100 lbs; a hollow one less.  Cost of aluminum is about $3 a pound.  Cost of powder is $16 a pound.  So assuming you were able to recover the shot, shooting is not prohibitively expensive.

Cost of surplus steel is around $1 a pound assuming you can find what you need.  Your project will require some machining and a lot of welding.  And then you would need the mount (above figures are just the barrel.)  You would probably need at least another 250 lbs in the mount.

And then you need the patience to only use aluminum balls and 1 pound of powder per shot.   ;D
GG
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Offline entsminger

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Re: Anyone made a 10 inch mortar lately?
« Reply #69 on: August 31, 2010, 04:20:55 AM »
  I have several welders including a mig and oxy-acct. and a plasma cutter etc etc. They call me McGyver as I can build just about anything that I put my mind to. I've built boat trailers and exercise machines out of scrap and many other things and can weld just about anything. I'm not a certified welder so I might have to have some else weld up the barrel end like I've seen others do with bowling ball mortars made of a piece of pipe. I have tons of scrap steel and can get it if I don't have  it. What I can't find I'm sure is a barrel or piece of pipe that is strong enough to shoot a 13 inch aluminum ball, especially when I have no idea what I'm looking for? I've read enough to know that the liner or barrel needs to be super tough like a battle ship cannon if it is to shoot something. All I'm asking for is a ball park figure for roughly a 30 inch long liner/barrel that is strong enough to pass safety tests to throw a 12 or 13 inch aluminum ball with one pound of powder. I'm sure I can mount the barrel liner in my tank with no problem.  What is such a piece of pipe,what are the specs for it, what would it cost and where would I get it?

  Scott

Offline GGaskill

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Re: Anyone made a 10 inch mortar lately?
« Reply #70 on: August 31, 2010, 11:31:45 AM »
I could take you to my metals dealer with no difficulty; unfortunately, he is in South El Monte, LA County, Peoples' Republic of California.  You will have to look around your area for a surplus metals dealer and go take a look at his inventory.  Look for tubing, not pipe.  And seamless is best.

I know this stuff is available as my guy has some.  But unless you are coming to southern California, it would be impractical to ship.

Also, check your PM.
GG
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Offline Cannoneer

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Re: Anyone made a 10 inch mortar lately?
« Reply #71 on: August 31, 2010, 12:32:32 PM »
    By the way, there a a great bunch of cannons and mortars to be seen at Ft. McNair ( tons of them) in Washington DC. they had at least three 13 inch mortar barrels and one of them was recently removed by the army to go to NY somewhere. The local Govt. historian that I personally know suspects that the one removed to be the original Dictator but the Army is not forthcoming in answering questions about it. When they pulled it up off the ground the Army would not let him look at the numbers on the barrel.

Sorry Scott, but this post has nothing to do with any practical aspects of making a repro 13-incher.

The history of the "Dictator" can get complicated very easily, so I'm going to try and make this short and sweet. Edwin Olmstead (famed CW artillery historian) was convinced that a sketch of the 'Dictator' drawn by a Union Private on 7/13/1864 had the valid weight of the mortar recorded on the sheet, (17,186 lbs.) unfortunately Pvt. Herbert E. Valentine didn't leave any notes on any other numbers that were on the mortar. According to military documents only three "Army" 13-inch mortars, and two "Navy" 13-inch mortars had this same weight marked on them, and it's exremely unlikely that a U.S. Navy mortar was used in the Federal siege of Petersburg, VA.

A 13-inch M1861 mortar on a monument in Hartford, CT was for many years thought to be the Dictator, but the weight of that mortar is marked as 17,197 lbs., so now (because of the weight and some other reasons) the general consensus among historians is that this is definitely not the Dictator.

The "Army" mortar that Scott mentioned as having been moved from Ft. McNair, Washington, D.C. (where it was partially buried muzzle down in the ground) to Ft. Hamilton, in the borough of Brooklyn, New York, NY is marked with the right weight of 17,186 lbs., but because of various other facts it is not considered likely that this is the Dictator.

There are now 27 known surviving M1861 13-inch mortars, and the only one with a marked weight of 17,186 lbs. is the mortar now located at Fort Hamilton, in New York City.

In the final analysis there doesn't seem to be any certain way to know if the "Dictator" does or doesn't exist, short of some authentic documentation coming to light that has the "registry number" and/or "the foundry number" of the 13-inch mortar that bombarded Petersburg in 1864/65 recorded on it.





   




RIP John. While on vacation July 4th 2013 in northern Wisconsin, he was ATVing with family and pulled ahead of everyone and took off at break-neck speed without a helmet. He lost control.....hit a tree....and the tree won.  He died instantly.

The one thing that you can almost always rely on research leading to, is more research.

Offline Zulu

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Re: Anyone made a 10 inch mortar lately?
« Reply #72 on: August 31, 2010, 12:59:07 PM »
BoomJ,
You never seize to amaze me with the information you come up with.  Thanks for an interesting post.
Zulu

Edit,
BoomJ,
Do you have access to a copy of the National Registry?  Do you have a copy of "The Big Guns"?  If so, is that one worth the $80 they are asking for it?
I'm still Zulu
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Offline Cannoneer

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Re: Anyone made a 10 inch mortar lately?
« Reply #73 on: August 31, 2010, 02:27:14 PM »
Thanks Zulu; I do have the book and a 2009 National Registry, and my opinion is that if someone's really interested in 19th century American large bore artillery, then "The Big Guns" is invaluable.
RIP John. While on vacation July 4th 2013 in northern Wisconsin, he was ATVing with family and pulled ahead of everyone and took off at break-neck speed without a helmet. He lost control.....hit a tree....and the tree won.  He died instantly.

The one thing that you can almost always rely on research leading to, is more research.

Offline entsminger

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Re: Anyone made a 10 inch mortar lately?
« Reply #74 on: September 01, 2010, 02:59:28 AM »
The "Army" mortar that Scott mentioned as having been moved from Ft. McNair, Washington, D.C. (where it was partially buried muzzle down in the ground) to Ft. Hamilton, in the borough of Brooklyn, New York, NY is marked with the right weight of 17,186 lbs., but because of various other facts it is not considered likely that this is the Dictator.
  ==Scott==
   All I know about it is that the Official base Historian ( who is a friend) suspected that the mortar that was moved to be the original Dictator especially when he asked the army to look at the muzzle to confirm his suspicions when they lifted it from it's position nose down in the mud and they wouldn't let him look at it. Now that I have become aware that the one in Petersburg is a fake ( thanks to this forum!) and that one was moved from Washington to NY it makes me furious that this mortar didn't go to Petersburg where a real mortar deserves to be!!!!!!!!

Offline entsminger

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Re: Anyone made a 10 inch mortar lately?
« Reply #75 on: September 02, 2010, 07:46:47 AM »
start checking the cost for a piece of 13" diameter steel thats 35" long and you will be a little closer than you are now to estimate the cost for your build
 

  ==Scott==
  Yes that's easy if it's just an ordinary piece of pipe but that's not the case is it with making this thing shootable. I'm talking a 13 inch 35 inch long pipe that is seamless etc etc that makes it strong enough to withstand shooting a aluminum ball. I have no idea what that is, how thick or strong it needs to be , what such a piece of pipe might cost and  where to look for such a thing. Isn't there someone on here that can give me some ball park answers to these questions?? Cost is my biggest question at this point. If it's to much I'll just have to forget making it shootable.

Offline entsminger

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Re: Anyone made a 10 inch mortar lately?
« Reply #76 on: September 07, 2010, 03:53:58 AM »
==Scott==
   Thanks George for sending me what looks to be an AutoCAd type drawing of a 13 inch mortar barrel for my propane tank cannon. Looks like you did alot of work on it and I appreciate that. Basically it looks like a heavy duty liner with some kind of bulbous heavy iron area near the breach? Can't say I understand exactly what's going on in the drawing but I'm guessing it's like a banded barrel with a hugely thick area where the fuse is?
  I think I'm at the same point I was last year. I get excited about making this thing shoot and I ask the only dumb questions that I know to ask and  with the exception of George get very  little usefull answers in return. This site is my only outlet to learn about making a shootable mortar, I'm not joining clubs or going to shoots. I guess I'm right back to where I was last time, giving up on the idea of making it shoot.

Offline Double D

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Re: Anyone made a 10 inch mortar lately?
« Reply #77 on: September 07, 2010, 05:05:02 AM »
Scott,

I don't know what to say,  You have got some extremely useful information and good ideas from us here on the board. I think you are having a difficult time visualizing whatn we are saying.  

You need to expand you exposure and get some hands on experience and we have suggested how you can do that.

I wish I were still in Virginia, because I would get with you and help you build the gun.

Perhaps George can post the drawings and we can help you understand them.  
 


Offline entsminger

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Re: Anyone made a 10 inch mortar lately?
« Reply #78 on: September 07, 2010, 09:30:50 AM »
Scott,

I don't know what to say,  You have got some extremely useful information and good ideas from us here on the board. I think you are having a difficult time visualizing whatn we are saying. 

You need to expand you exposure and get some hands on experience and we have suggested how you can do that.

I wish I were still in Virginia, because I would get with you and help you build the gun.

Perhaps George can post the drawings and we can help you understand them. 
 
===Scott==
 I mean how hard is it to just give me a ball park idea of what a 30 inch piece of  seamless pipe or whatever is needed that is capable enough to be used to shoot  an aluminum cannon ball might cost or where to get one?  Seems like a simple request but no usable answers ever come forward. I've been to cannon shoots and most guys there bought their guns and wouldn't have a clue what I might need to make mine so that's been a waste of time as far as how to make mine shootable. I just hoped for a ball park price idea so I could either start thinking about this or forget it. 

Offline GGaskill

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Re: Anyone made a 10 inch mortar lately?
« Reply #79 on: September 07, 2010, 10:09:56 AM »
I mean how hard is it to just give me a ball park idea of what a 30 inch piece of  seamless pipe or whatever is needed that is capable enough to be used to shoot  an aluminum cannon ball might cost or where to get one?

It's harder than it sounds since none of us live in the DC area and therefore are not familiar with what kinds of metal yards are around there.  I can get a price from my local yard but it is not too relevant to DC unless you want to ship 500 pounds across the country which might triple the cost.

For guessing purposes, figure $1 per pound for surplus steel.  I guess there is at least 800 pounds in that design plus the fabrication costs.  If you can't spend at least a grand on this, I think you can't get it done unless you stumble over something free (which does happen occasionally.)  And that's just for materials.
GG
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Offline Double D

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Re: Anyone made a 10 inch mortar lately?
« Reply #80 on: September 07, 2010, 11:23:04 AM »
If you have plans just get in you car and start visiting steel yards and asking if they have what you need.  Show them the plans.  If they can't help you, ask them to refer you to some one.  Ask if they know any repair shops that might use that kind of materials you need.  Go visit  the referrals.  If the referral says no ask then if they have a referral. 

You are wrong about those guys at the shoots.  A lot of them built their own guns especially the 24 pound Confederate coehorns. Those guys don't have a clue who you are and are going to be less than open with you if you just walk up and start talking. My work while I was in the area did give me time to join any of the mortar teams.  After a couple of visits they saw I had a real interest, I was offered a spot on several teams. The are always looking for team members.  Those folks also provided me a contact in Norfolk who provide me with plans for the building the 24 PDR and 12 PDR coehorns.  When I talked to the fellow in Norfolk, I asked where I could  some of the stuff I needed.  He told me to contact a company in Winchester that did aluminum castings. 

I contacted that company and the were will to take my mould and cast aluminum balls with the left over from there castings at the end of the day.  Sadly I got a transferred to South Africa before i go the mould.

The Guy in Norfolk also told me about a guy in Pennsylvania who built most of the 24 PDR's used at Fort Shenadoah and who also built a couple of 8 inch mortars. He gave a name of a company in NJ who specialized in scrap metal of loar rounds.

I a long time ago when I was a young rookie cop want to become a hot shot detective, I worked with an old timer real detective.  He gave me a little placard that had these letters on it. GOYAKOD  He said that if I wanted to be come a good detective, I had to make that my motto.  GOYAKOD, get off your  butt and knock on doors.  Believe me he practiced what he preached and clear a lot of cases.

We have provided you with some good advice and lots of information, and now you even have a set of plans, it's time for you to GOYAKOD.

Now if you can't understand the information you have been provided, then perhaps building a mortar isn't for you. You will have to find some other way to get one.

Offline entsminger

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Re: Anyone made a 10 inch mortar lately?
« Reply #81 on: September 08, 2010, 03:54:41 AM »
Now if you can't understand the information you have been provided, then perhaps building a mortar isn't for you. You will have to find some other way to get one.

   I can take an engine apart and put it back together like nothing. I can weld just about anything. I can sculpt figures and repair just about anything ever made but I just can't get a grasp on what is required to make this mortar shootable. I don't think it's me not understanding so much as it's that you guys are so far above me in this stuff that it's hard to dumb yourself down to my pathetic level. You're so used to people that understand what you are talking about that's it's hard to come down to my level of stupidity at building cannons. I don't have the time or where with all to join groups or whatever at this time.To many other responsibilities with family and job and all. I was hoping I could learn what I need from here but I guess I can't. Thanks for trying.

  Scott

Offline Double D

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Re: Anyone made a 10 inch mortar lately?
« Reply #82 on: September 08, 2010, 04:44:46 AM »
I don't get it.  George provided you with a set of plans. You go get the metal and put it together and you have a mortar?

Offline entsminger

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Re: Anyone made a 10 inch mortar lately?
« Reply #83 on: September 08, 2010, 08:52:12 AM »
  What George gave me was great. He put in a ton of work but I still don't know what alot of it means on the drawing and have no clue where to get such materials or what  a seamless liner that is 30 inches long might even cost. I guess I need someone who can come to my Neanderthal level and explain it in basic laymens terms. I'm assuming you can't just go to some junk yard or scap yard and get a super tough seamless liner that would pass an official cannon inspection. Wouldn't it have to come from some kind of steel fabrication house or something where pipe is made to super specs? ? Sorry for being such a numbskull but that's just the way I am.

  Scott

Offline dan610324

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Re: Anyone made a 10 inch mortar lately?
« Reply #84 on: September 08, 2010, 10:23:55 AM »
well I would guess that you aint stupid , just that its way out of your normal interest field
just try to find more info and learn more .
I can promise that the satisfaction to have built your own piece is hughe
Dan Pettersson
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interested in early bronze guns

better safe than sorry

Offline GGaskill

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Re: Anyone made a 10 inch mortar lately?
« Reply #85 on: September 08, 2010, 11:30:07 AM »
OK, here are the plans I sent to Scott.  They are SOP (seat of the pants), not engineered, but should be a good start, at least.

 

Basically there is a large chamber piece attached to a cylindrical piece and to two sets of "wings" that connect to the trunnion pieces.  The wings are steel plate welded on each end to the trunnion and the chamber piece.  There are also two bars going between the trunnions and next to the cylinder that are supposed to resist the trunnions moving together from recoil reaction.  I am assuming the propane tank is not very thick and therefore did not rely on it contributing any strength to the overall assembly.  If it has significant strength (thickness), you could add braces at the rear of the chamber piece to transfer some of the recoil force through the tank body to the trunnions.
GG
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Offline entsminger

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Re: Anyone made a 10 inch mortar lately?
« Reply #86 on: September 09, 2010, 03:16:48 AM »
  Hey George, this drawing is great! How did you do it, in some kind of auto cad program? I think the problem is that it's just hard to communicate these kind of things via the internet. I need to talk to someone like you in person. Please let me know if you're ever going to be in the Washington DC area on a work related job or just a visit to see what a mess this government is, ha ha , and maybe we could get together for a few minutes and you could better explain this stuff to me? Right now with my son in college I have no money to do anything so this is all food for thought untill he graduates. The tank I have has two ends to it which is enough for 2 mortars so for now I'll probably just make one that is just for looks and then with the other end I might be able to try and make one that is shootable? Hopefully in 3 years or so I'll have it figured out? My phone number is 703 528 1548. Please drop me a line if you ever plan to come this way.

  Thanks
  Scott Springston

Offline GGaskill

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Re: Anyone made a 10 inch mortar lately?
« Reply #87 on: September 09, 2010, 10:48:00 AM »
I was in the NY metro area earlier this year.  May get back there next year but no immediate plans.  I'll keep it in mind, though.

I use a program called IntelliCAD, a free version from Y2K that is an AutoCAD clone.
GG
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