Author Topic: How to Add Sights to Your Cannon without Drilling Holes.  (Read 2571 times)

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Offline Double D

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Re: How to Add Sights to Your Cannon without Drilling Holes.
« Reply #30 on: November 05, 2007, 07:51:34 AM »
I found your Yaw control...you put it in the forest with a bunch of trees.  Here it is right here in plain sight.




 You want the scope mounted top dead center for zero roll  around the bore center line.   You want the scope mounted parallel with the center line of the bore front to back for zero pitch. (Actually you don’t because bullets don’t travel in a flat straight line but that is another topic)   And you want the center line of the scope mount  centered right left front to back with the center line for zero yaw.

If you don’t minimize roll, pitch and yaw the center line of your scope won’t point to the some point  as the centerline of the bore.

Now I looked at your mount and saw the four pressure balls and I saw the forest “pitch”  when if fact they are the trees- “yaw”.   Basically the four balls are the legs of a V-block with everything not touching cut away..   

What I overlooked is that it is generally  accepted in gun barrels the outside of the barrel is I concentric with the bore…Duh!

So carry on, ignore the daft almost  senior citizen.

Good thing I got that 500 server error yesterday, you should have seen the gibberish I typed.









Offline seacoastartillery

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Re: How to Add Sights to Your Cannon without Drilling Holes.
« Reply #31 on: November 05, 2007, 12:54:15 PM »
     Boy oh boy, you really had us going, Double D.  In between sessions at the drafting board, I would ask Mike, "What the heck are we missing here?  He even began some obtuse theories about how spacecraft fly and such.  I went over everything about that fairly simple sight base in my mind at least a hundred times.  Mike even offered this,"Maybe he's a former Air Force pilot with some astronaut training, which means he knows twenty-five times as much about "yaw" as we will ever know?"  Well, we sure are glad that you entered your last post.

     Your V-Block analogy is right on the money!  And also, the fact that the concentricity of the bore to the outside diameters is less than .005", means that you can accurately assume that yaw would be zeroed and adequately controlled as long as your sight axis is coincident with what mortar-men in the 1860s called the "plane of fire" which was a vertical plane 90 deg. from the trunnion axis which bisected the mortar's mass of metal and encompassed the bore axis, the sight axis and the trajectory of the projectile.  The honesty of your post is very, very refreshing and does you great credit!  Thank you.

     Lance, we do expect to see you and Tim, both, in Montana in 2009.  We also expect you to show up with the fanciest darn sight base ever built AND a beautiful 1/7th scale Monitor Turret target with ALL the rivets and bolt heads and even that cable they had wrapped around the top edge.  Two perfectly scaled 11-inch Dahlgren muzzles within the darkened cannon ports would be icing on the cake!!  We can hardly wait to see it!!!

Regards,

Mike and Tracy
Smokin' my pipe on the mountings, sniffin' the mornin'-cool,
I walks in my old brown gaiters along o' my old brown mule,
With seventy gunners be'ind me, an' never a beggar forgets
It's only the pick of the Army that handles the dear little pets - 'Tss! 'Tss!

From the poem  Screw-Guns  by Rudyard Kipling

Offline Double D

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Re: How to Add Sights to Your Cannon without Drilling Holes.
« Reply #32 on: November 05, 2007, 02:58:47 PM »
Sights? Montana? 2009? Huh?  We aint doing no bench rest shooting.  Peep and post at the most!  Well wait we could shoot gophers!!!

Offline lance

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Re: How to Add Sights to Your Cannon without Drilling Holes.
« Reply #33 on: November 05, 2007, 03:26:18 PM »
 dog gone it! if i go to all the trouble to make a sight base and fancy target, i'm bringing them. Hey! i like gophers, we have a small villiage of them at the zoo about 40 miles from here. they are too cute to shoot ;D ;D ;D Now, Tim won't shoot at my cardboard silhouettes, say's he don't shoot people......... you guys still want us to come? ;D ;D ;D
PALADIN had a gun.....I have guns, mortars, and cannons!

Offline Double D

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Re: How to Add Sights to Your Cannon without Drilling Holes.
« Reply #34 on: November 05, 2007, 06:30:01 PM »
You can bring you scope Lance!  We will have targets to shot that you will enjoy.  We might even play Bingo...