Bored barrel blanks

[Iron Balls]

I have been going through the old posts. I am back 44 pages and I have a lot of questions about things I have read. But; There was a subject in which it seemed that some vendor was offering barrel blanks with the bore already done. I did not see anything like that in the stickies, but I can't find things in the food store either.
So.. Is this something that is done? Do some people start with a bored blank? I have access to an engine lath but I am not sure about the boring of a barrel. I do not know if a local shop could bore a barrel to the proper specs. Is this something a good local shop would be able to do? I am sure that I could turn a howitzer if I didn't have to bore.

[Iron Balls]

Another thing; I have seen mortars pictured with the projectile sitting half way out of the tube. Is this by design or is the tube double shotted to display the projectile?

[seacoastartillery]

     We, Seacoast Artillery Company, have been working on getting our rifled liner or sleeve product figured out for about a month now. Not too much time for Petard target building, but we will chip away at that Special Project gradually as we have time.  First, we will let you know about some changes we have decided on due to many reasons, mainly customer cost.  Mike and I have always thought that the price point for these 1.0000" bore sleeves should be $399.00, so we have designed them, looked high and low for the best materials and have purchased efficient tooling with meeting this 1" bore rifled sleeve price always in mind.  Any less and we would not bother to make them and any more and you rifled cannon hopeful would probably not buy them.  When we expand the line to include 1.750" Bore dia. rifled sleeves the price will be $499.00  The reason we do not anticipate making any cannon blanks is that, because  the large volume of additional steel stock in the form of rounds and the gundrilling and the reaming necessary, will drive the cost up to $799.00 to $1,000.00 and that is way beyond the price point we think is correct for this type of product.  Of course, if someone insists on having this type of ordnance, we can provide it.

    The lengths on the 1.0000" bore dia. sleeves will be 28" long.  This will be adequate for a full 1/3 scale field gun of the Civil War period.  The stock we have is 30" long but we always remove about 2" to rid ourselves and the customer of any variation in the rifling nearest the muzzle, because of rifling head emergence.  The wall thickness will be .385" minimum to .625".  The larger size can be turned down by the installer if necessary to .375" wall thickness.  Any wall thickness less than .375 will void the warrantee.

Tracy and Mike

[Double D]

Plugged our unplugged?

[seacoastartillery]

    Douglas,    In the sleeves which we will be assembling after rifling, a threaded breech plug will be torqued into the tube's breech at 75 foot pounds, bringing two 1/8" wide annular steel sealing surfaces, parallel to .0001" together permanently, making a gas tight seal.  We will use Locktight, threadlocker RED on the threads prior to torquing, lending further permanence to the assembly.

Tracy

[Double D]

    Douglas,    In the sleeves which we will be assembling after rifling, a threaded breech plug will be torqued into the tube's breech at 75 foot pounds, bringing two 1/8" wide annular steel sealing surfaces, parallel to .0001" together permanently, making a gas tight seal.  We will use Locktight, threadlocker RED on the threads prior to torquing, lending further permanence to the assembly.

Tracy

Will they be welded per the N-SSA recommendation?

[seacoastartillery]

    Douglas,    In the sleeves which we will be assembling after rifling, a threaded breech plug will be torqued into the tube's breech at 75 foot pounds, bringing two 1/8" wide annular steel sealing surfaces, parallel to .0001" together permanently, making a gas tight seal.  We will use Locktight, threadlocker RED on the threads prior to torquing, lending further permanence to the assembly.

Tracy   

Will they be welded per the N-SSA recommendation?   

     And ruin our fine machining? Absolutely not.   We are closing our tubes the same way that millions and millions of musket breeches were secured over the ages.

Tracy

[Double D]

Well Muzzle loader barrels and breech plugs are on the outside of the gun secured by barrel tenons, tangs and tang.

You will provide us with the the steel information for welding if we choose that route.

I guess the N-SSA rule would not apply to these liners as they are not for full scale use.  AAA however does recommned pinning.  Will there be enough room for pinning

My liner is going to be epoxied into a blind hole and I want to be able show pictures of the liner as may be required if I were attend am AAA event.
 

[Iron Balls]

If a liner is epoxied into a blind hole, where is it going to go? Each time you fire the gun, seems to me, would tend to ensure that it is seated. Is it possible to machine a press fit? Put the barrel outside in the sun for a few hours and fill the liner with dry ice?

[seacoastartillery]

     Sure, DD, we can drill a hole and put a dowel pin into it as there is plenty of room to do so.  If that's what the AAA requires, we would be happy to accommodate you, and we won't even mention all the reasons that this extra pin is pure silliness.

If a liner is epoxied into a blind hole, where is it going to go? Each time you fire the gun, seems to me, would tend to ensure that it is seated.

Is it possible to machine a press fit? Put the barrel outside in the sun for a few hours and fill the liner with dry ice?

     Look DD, even the new guy gets it!       Excellent, Iron Balls, you sir are a logical thinker!       Most of you already know that DD knows all this stuff too, he just wants to be prepared to present credentials in case that is called for some day.  There is nothing wrong with being prepared.  If anyone would like to know why this extra pin is simply there to satisfy the AAA's lawyers, I'll tell you, if not, fine.

     Iron Balls,     Listen up, that one in blue above, well sir you've got press fit mixed up with shrink fit.  Yes it is possible to machine a liner so that it will be a press fit with the bore of a cannon.  The reason it is not done is that it is difficult to pull off without a collapse of the liner under hydraulic pressure.  The reason that your other method is rarely used by sane mechanics is that they know how little clearance the method you suggest would give you to work with.  It's far easier to work with 1/32 clearance all around in a 1.000" or 1/16" all around with a 3.000" and a half pound of well mixed epoxy!

T&M

[Cannon Cocker]

     .  It's far easier to work with 1/32 clearance all around in a 1.000" or 1/16" all around with a 3.000" and a half pound of well mixed epoxy!

I've used less clearance than that and been able to push a 40" long, 2.25" bore liner into a barrel by hand, coated with very thick  (much thicker than JB Weld) aluminum impregnated epoxy.  I had a press set up to push it in if I got stuck, but never needed it.  If you drill the pilot for a vent first, it lets out the air and extra epoxy at the bottom of the bore.  I still recommend having hydraulics ready because you DON'T want to have it stick before it's all the way down.  Dry fit it and mark the full depth on the end of the liner before starting.  and mark it really well because it is going to be covered with goop soon. 

After it hardens, you HAVE TO (must) use a brass, copper, or steel allthread vented bush (rather than drilling a straight vent) because of the possibility of gas ballooning in between the liner and the barrel. 

Also, there is no better way to close a breech than the one described above by Seacoast.   

[Iron Balls]

  /

[Double D]

Yes my point is to have the liner and barrel satisfy safety regulations of American Artillery Association at minimum.

[Iron Balls]

Yup. If you want to play, you gotta play by the rules. I can see where your coming from.

[Doc Brown.]

I have been going through the old posts. I am back 44 pages and I have a lot of questions about things I have read. But; There was a subject in which it seemed that some vendor was offering barrel blanks with the bore already done. I did not see anything like that in the stickies, but I can't find things in the food store either.
So.. Is this something that is done? Do some people start with a bored blank? I have access to an engine lath but I am not sure about the boring of a barrel. I do not know if a local shop could bore a barrel to the proper specs. Is this something a good local shop would be able to do? I am sure that I could turn a howitzer if I didn't have to bore.

Heres a blank barrel you could easily turn for fun! Found it on fleabay.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=321142956605

[Iron Balls]

 
Heres a blank barrel you could easily turn for fun! Found it on fleabay.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=321142956605

Yeah. That's a beauty.

[Zulu]

I have been going through the old posts. I am back 44 pages and I have a lot of questions about things I have read. But; There was a subject in which it seemed that some vendor was offering barrel blanks with the bore already done. I did not see anything like that in the stickies, but I can't find things in the food store either.
So.. Is this something that is done? Do some people start with a bored blank? I have access to an engine lath but I am not sure about the boring of a barrel. I do not know if a local shop could bore a barrel to the proper specs. Is this something a good local shop would be able to do? I am sure that I could turn a howitzer if I didn't have to bore.

Heres a blank barrel you could easily turn for fun! Found it on fleabay.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=321142956605

Dock,
Those are your thunder mugs.
Zulu

[MKlein]

What is going on in this photo?
Hot Coffee?

 
 
 
 
 
 
 
 
 
 
 

[Doc Brown.]

Not mine that guy stole my identity. If I had to guess what that fire is id say the base got heated up to fit the barrel but that's just a guess.