Optical sights for the 1/4-scale Napoleon (formerly: "Tactical Napoleon")

[Terry C.]

NOTE (8/4/08): I've changed the title of this thread. "Tactical Napoleon" was meant to be humorous, but it isn't very accurate or descriptive.
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This is my new scope mount. I'd hoped to have it polished and have better pictures, but my schedule and the weather haven't cooperated. Inspired by Tracy & Mike's scope mount for the Parrott Rifle, it began as a concept...




This is an early drawing, a few minor details were added since this was converted to JPEG but the basic dimensions are pretty much unchanged.  The baseplate is a piece of 1/2" x 2" aluminum flat bar 10" long.  The unit straddles the barrel and rests on 1/4-20 brass acorn nuts.  The two in the rear are fixed, the two in the front are adjustable and set the mount parallel to the bore. The brass hook rests against the rear face of the cascabel and positions the unit fore/aft.  The smaller (10-24) acorn nut on the levelling leg rests on the trunnion rimbase. I put it where it is so that I can stabilize the mount with my left hand while I aim the gun with my right.






I used two-piece Weaver bases and I have an extra pair of holes drilled in the baseplate for a wider range of spacing.




The scope in the first photo is a Tasco Bantam 2.5X scope that I bought an clearance sale at Wallyworld. I have a 4X Busnell that may be available in the near future (right now it's in-use) if I feel the need for higher magnification.

So is it finished?

Aside from the additional polishing I plan to do, I also may change the hook on the rear. It didn't come out as well as I wanted so I'm going to go back to the drawing board on that. For now, though, it's fine and works well.

And then there's the laser...
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Oh yeah, almost forgot. You can click on any of the images to open a larger version.

[Evil Dog]

And then there's the laser...

I'll vote for that.

[Victor3]

 Cool beans. Might want to add one of these doo-dads...

http://www.midwayusa.com/Eproductpage.Exe/showproduct?saleitemid=498458

[Double D]

Change the hook to a locater pin that drops into the vent.

[seacoastartillery]

     Terry,   Nice job; looks like it will work just fine.  We need to see holes in the target pics next!

     Double D,   It's physically impossible for the locator pin and the fuse to occupy the same space at the same time.  No?

Regards,

Mike and Tracy

[Double D]

          Double D,   It's physically impossible for the locator pin and the fuse to occupy the same space at the same time.  No?

Regards,

Mike and Tracy

Ah duh, yah......

...then how about making the trunion points v-blocks?

[Terry C.]

And then there's the laser...

I'll vote for that.

Every vote counts... 




While the laser looks high-tech, its purpose is not precision aiming. It's there to allow me to return the piece to battery so that the target is already in the field of view, before I have to bend over and sight through the scope.

I turned 50 last Tuesday, I don't want to do any more bending than absolutely necessary.

[kevthebassman]

It's ridiculous!  Blasphemous!  Impractical and unnecessary!




















I love it!

[seacoastartillery]

     Terry C.   Wait!  Before you change that hook, let's take a closer look at Double D's suggestion. 

     First we feel forced to answer kevthebassman's comment.  Yes we understand the import of his posting; we did notice the 3 words at the bottom, however, we feel complelled to say that Mike and I believe that the use of our sight base or Terry's is the following:

          1)  Ridiculous, no, but wise, prudent and Bill O'Reilly would say, "Perspicacious".
          2)  Blasphemous, no, but rather, faithfully repeatable.
          3)  Impractical, no, but simply functional.
          4)  Unnecessary, no, for us or anyone who DOES NOT want to drill holes in their cannon, essential.

     I bet both Terry C. and the Colorado Cannon Guys all appreciate your comments, Kevin.  Thanks.

     We thought a lot about Double D's v-block comment: 

...then how about making the trunion points v-blocks?

     Then we began to see the wisdom of his idea.  This v-block idea would do all these things:    Stop sight base motion along the -X- axis
                                                                                                                                           Be adjustable in the -Z- axis to control sight base leveling.
                                                                                                                                           Be easier to make.

     Now you could do this with a single rod with a "V" shaped tip OR you could use two acorn nuts side by side which would duplicate one half of an inspector's "Ball Block" which we used frequently in Aerospace work.

     Ignor all this if you already have an improved "hook", which will work perfectly well.

Regards,

Mike and Tracy
     

[Double D]

Wisdom? Is that what people meant when they called me a wise a....well maybe not.

[Cat Whisperer]

Stability and repeatability.

Vee block locators are good.  AND comparable in concept to the device shown - just changing the locating from the tube to the trunions.

One can, of course, go back to the standard 3-2-1 locating princiiples.

Used to control the location of two objects in relationship to eachother in the 9 directions of movement.  (3 axes X,Y, Z and axial and 2 directions of rotation in each)

Perhaps worth a topic (and ILLUSTRATIONS) of it's own.

[Terry C.]

Sorry I've been neglecting this thread, I've been chasing electrical gremlins through the house for the past few days.

The vee-block is a very good idea, that's why I considered it early on!

Unfortunately, the indicating point is the trunnion rimbase. The rimbases are very narrow, just enough room on the very top (where it is widest, about 3/8") for a single point of contact. The rimbase narrows quickly, and is only about 1/16" wide at its narrowest (the centerline). I felt that there simply wasn't enough contact area on the rimbase for the vee-block.

The tailhook does a decent job. Most of my rantings about it were simply frustration. And the fact that it was all my fault didn't help.

Confession time:

The tailhook was supposed to be made of 1/4" brass rod, and adjustable. It is neither.

The piece of rod that I had which was supposed to be 1/4" in diameter, turned out to be an odd size that I mistook to be 5mm. No problem, a 13/64" drill would be close enough.

Except that it wasn't 5mm. It was .204" (yeah, now you measure...)

It would start in the drilled hole about 1/2" and go no deeper. So I got the (again) bright idea to cut a chisel point on the rod and spin it down into the hole.

Hmm, still tight, lets do it again. Still a little too snug, one more time.

Perfe... squeeeeeeeak!!! Oh, crap...

So now I had a piece of pretty brass rod, that is neither 1/4" nor 5mm, permanetly friction-welded into my baseplate.

Nothing to do but bend it and cut it off, and hope I got it in the right place. Fortunately, I did manage to bend the tailhook correctly, so that it positions the leveling leg on the rimbase. I even installed the hidden setscrew that I so carefully designed, for what that's worth.  It ain't doing anything, but it will keep the screw from getting lost.

And it works, it catches the rear face of the cascabel securely and positions the baseplate accurately.

But it isn't what I wanted, hence the frustration.

When I get another piece of rod, I plan to drill out the oddball piece (that's the only way to get it out) and redo the tailhook. It may not work any better, but it will give me the last laugh.

Next up is to machine an adapter so that I can use my laser as a boresighter. FWIW the little red laser isn't going to be of much use outdoors past the 25 yard range, it just isn't bright enough. Depending on how it performs (or doesn't) during the boresighting, it may or may not make it back onto the scope base.

[Terry C.]

I've decided to change the title of this thread. "Tactical Napoleon" was intended to be catchy and humorous. And it was, for a while.

We've gone past that now. I think a more accurate and descriptive title is in order.


For the record (for those that aren't already familiar with this gun) the barrel in question is my ¼-scale replica smoothbore 12-pounder Napoleon model of 1857. The gun tube is CNC-machined 1045 steel, and was purchased through Cannon Mania. This was before all the problems with them started.

The bore is to-scale, which gives it a diameter of 1.156". The projectiles are 1.125" diameter round balls that weigh 4¾ ounces cast from scrap wheelweights. They are cast in a brass ball mold from JT Moulds in the UK.

[dominick]

I liked the Seacoast Artillery/Terry C. style scope mount, I thought I would give it a try. I made it from steel of course.  I built it for a customer's cannon who requested sights to be installed.  I told him about this deal so we will give it a try.  Thankyou Seacoast and Terry.

[Terry C.]

Looks great!

What power scope are you using? Is the one in the photos going with the gun or will they be supplying their own?


I still haven't gotten mine boresighted. The weather has been mostly clear for a change (at the expense of Texas/Louisiana) but now we are suddenly swamped with work.

"Swamped." Get it? We're in the ... oh, nevermind. 

We're also shorthanded, one of our guys got into a bit of trouble and is currently in a court-ordered substance abuse rehab clinic (in lieu of jail time). But that's a whole 'nuther story.

Hopefully before the weekend I can get break away long enough to machine the the bore adapter for the laser.

[dominick]

The customer will be supplying his own scope.  I had a 4 power SKS scope laying around that I set on top of the mount for the photos.  "Swamped".  Same here.