Nano-mortar

[CU_Cannon]

Here is my latest creation.  I got the bug to build something really small after seeing copdoc’s little cannon.  I have dubbed it Nano-mortar.  I have to say it’s as much fun as my big stuff and much cheaper to shoot. 




It is 0.177 bore (BB size).  The bed is 1” long. 

It shoots well thought it’s not much for range.  I got about two feet out of a pinch (probably about a grain or two) of FFg. 



The muzzle blast from this guy amazes me.

Here is the drawing for those who are interested.  For the most part I stuck to the drawing.  The bed ended up thicke;r all I had was 1/2" steel.  The original plan was to plug weld the barrel on from the bottom.  Since the bed was thicker the drill would have broken though on the end.  I ended up tacking it from the top.  It doesn't look as good but it works well.  I’ll have to make another improved one. 

[Cat Whisperer]

COOL!

Did you have to use the CLOSEUP focal length option on your camera?

Are you going to do one in  ring-mount in silver or gold?

[copdoc]

NICE
and great photo.  I see why the powder can.  The action photo even looks like a big gun.

[Double D]

Oh no the micro cannon arms race is on!!!

[Rickk]

A sub-chamber no less!

Looks like something that anyone with a drill press could make... yup... the nano-race is on 

[seacoastartillery]

CU_Cannon, I love your nano-mortar!!  I wish my action photos turned out just half as good.  You and copdoc are very inspiring.  

[CU_Cannon]

"micro cannon arms race"

Sounds like it could be a fun contest.

The sub-chamber was just because.  On the next one I think I’ll do a straight bore.

Here are a couple of videos.  For some reason I couldn't get youtube to work so I found another video hosting site.  Let me know if it works.

http://www.mediamax.com/cu_cannon

[CU_Cannon]

I wish my action photos turned out just half as good

The secret to the action photos is to grab frames from the video.  You can really capture the muzzle flash that way.

[EL Caz 66]

Hey CU, Nice Nano Couldn't get the video to play...

[Rickk]

video worked for me... how about a night shot?

All you machinists out there... if I pick up a grade 5 bolt at the hardware store, can I drill a bore in it with a HSS or cobalt drill?

Is a grade 5 bolt a good material to use for a "nano"?

[Double D]

Watched the video....next time warn people to turn the volume down!!   

What are you using to worm the foil cartridge case out ofter firing? 

[CU_Cannon]

I uploaded some other versions of the videos.  The digital camera films them in .mov format I tried to convert them to .avi to make them smaller.  If they still don’t work for you let me know I’ll try something else.

Watched the video....next time warn people to turn the volume down!!   

What are you using to worm the foil cartridge case out ofter firing? 

The sound is much louder on the video.  In real life it wasn’t even a pop.

Worm?  I just reach my hand down the barrel to remove the foil.

Is a grade 5 bolt a good material to use for a "nano"?

I can’t see why a bolt wouldn’t work.  There is so little powder I don’t think it would be a problem.

[Rickk]

My biggest concern isn't that a grade 5 bolt is too soft to handle the massive powder charges, but too hard to drill.

I fear using cobalt drills for deep holes because I seem to break them easier than HSS drills. I do have a "Drill Doctor", so I can resharpen them untill they are virtually gone if they don't break.

Guess I'll have to run down to the hardware store this weekend and pick up some "hardware" to keep up with the nano-arms-race 

[Wraiths]

A table top mortar, that is pretty neat!  Just what a guy needs for those rainy days.
Just think what terrific fun it would be if you could find one of these in your cereal as the surprise toy in the box. 

[jeeper1]

Small enough to fit in a cellphone beltpouch with room enough for all the supplies and tools needed to shoot it. 
I wonder if it would then be classed as a concealed weapon?

[Cal.45]

Hi folks!                 


This is my first contribute to this forum but I watch the (bp mortar & cannon) discussion for years by now.
I am in the final preparations to build a golf-ball coehorn mortar. The calculations are done and I am pretty positive that it will be ready in late January. For a better understanding: I do not own a lathe, nor do I come from the metal machining business, so I need some help of a friend of mine for that.

Anyways:
After the Nano-mortar post from CU I felt the need to build my very first mortar NOW.
(yep DD, the race is on... Must be possible to get even smaller?)

It is solely done with a drill-press some files and emery paper.
Please excuse the rough appearance: I wished I could have used a lathe.





This mortar is designed to fire 3 Millimeter shotgun shot pellets (0.118 inch diameter).
I have been given those to melt down into bullets, but I found them to be pretty consistent in size so I kept them for a better use. 
The bore is done with a 3.2mm drill (0.126 inch); the mortar has a 2mm chamber (0.079 inch) for a maximum load of about 0.2 grains of black powder (Swiss #2).
The mortar will be welded onto the base (tomorrow), after that I can report how far the trajectory drives the shot. 



Sorry, but I do not own a GOEX can, so I placed a dollar note and a quarter in the photos for size reference.


Jorg
(from Germany)

[CU_Cannon]

Welcome 45.

I'm glad to have inspired you.  Your work looks good.  You don’t need much in the line of materials to build one or as you have shown equipment.

I think the biggest limiting factor is ignition.  Once your vent is 50% the bore diameter you really start to lose efficiency.

My biggest concern isn't that a grade 5 bolt is too soft to handle the massive powder charges, but too hard to drill.

I have drilled bolts before.  They aren’t that bad to work with.  You should be able to drill one fine. 

Just think what terrific fun it would be if you could find one of these in your cereal as the surprise toy in the box.

[GGaskill]

I got about two feet out of a pinch (probably about a grain or two) of FFg.

Probably should use FFFFg if you are going for max range.

[copdoc]

Darn, it's contagious as the flu.  Because of the flu i'm still at work and not working on my little cannon.  After flu season I am going to build a mini mortar unless I get one in a box of Greybeard.

[Rickk]

Cal.45 , what size is your fuse hole?   I am guessing it is less than .062.

If so, you will have to tell us how you managed to light it.

[jgalar]

Unless you have a permit to carry a concealed  cannon I would be careful about how I carried those things.

[Cal.45]

Hi again!

I  AM  INFECTED !!!

I just finished test-firing the pico-mortar. And it does work!
But first an update on finishing this little beauty:

After welding it to the base (being done from the bottom, by filling a bored hole: this way its not visible AND possible at all) the mortar was that hot, that the bluing in oil did work out fine. Just take a look at the picture below (ready for firing):



Anyways. I started with a load of about 0.2gr Swiss #2 but this did just a sizzling sound, so from the next shots on I used Swiss #1 (which is even finer in granulation: about 0.011 to 0.015 inch) which produced a nice snapping.
For Rickk and CU: The touch hole is 0.5 millimeters = close to 0.02 inch (that makes it about 16% of the bore diameter (if one may still call it so).
Priming was done by filling the touch hole granule by granule; sweaty hands help maneuvering these tiny particles in place.
First I wanted to enlarge the touch hole to fuse diameter and keep the rest at the smaller diameter (to keep some pressure) but the wall thickness is that small, that this was not possible.
Ignition with a lighter proofed to be better than trying to do it with a match: the flame produces soot but therefore does not function (kept them as size reference on the photo though).

Whatever. At first I thought that the shot would barely leave the muzzle: wrong!
Firing from the kitchen table I shot dimples into the door! This was 2.5 meters (8.2 feet) away! By the trajectory (angle of the mortar and height of impact) this means an estimated firing distance of 6 meters (about 20 feet): I would never have guessed this to be possible with a piece that has a barrel length of just 8 millimeters (0.315 inch).

Boy, does this little is fun to shoot with!

I did take a small video with my camera as well (bad resolution though).
The muzzle blast is most impressive taking in respect the tiny load.



By the way: the video is about 2.1 megabytes (*.mov-file) and it would take me ages to upload (I surf the web just with an analog modem still), does anyone know a tool to cut the important part out of the file (and/or convert it to be smaller in size), so that I may provide it?


I need to do a cannon the next time...  

[CU_Cannon]

Great shot!  You probably don’t have much hair left on you knuckles.

You can do some limited video editing with quick time player.  You can trim the video and convert it to a few different formats.

The finest powder I have is FFg.  I tried to patch the ball today to see if I could get a little more range out of it.  I didn’t have much luck.  The ball didn’t even leave the barrel everything went out the vent.  I guess it is a little too large.  The next one may need to use your method of ignition.


Well we have two.  Anyone else going to join the madness? 

[Rickk]

I stopped at the hardware store tonight and picked up a couple of 3/8 inch, grade 5 bolts, a few 3/16 inch drillls (a tight BB size bore) and a couple of 5/64 inch drills for 1/16 inch fuse. My favorite hardware store hires hot cutties to work there to help compete with Home Depot, so I am always looking for a reason to go there anyway 

Just gotta find some free time.

The plan is for a Coehorn. I am going to make the base out of wood. I am planning on either MIG'ing or brazing an 1/8 inch steel rod  trunion to the base... not sure which method yet. If it looks too small when I am looking at it to MIG, I'll probably braze it. I figure I can cut some strips of copper flashing for trunnion caps, using brass brads to attach them.

Firing from the kitchen table I shot dimples into the door!

     "Dimples" is plural, not singular. Cal.45... are you married? If so, your wife is way more understanding than most !

[Cal.45]

Well, I found me some shareware converter and did shrink the video down to the interesting 2 seconds, so it is now a 350 Kbyte *.avi-file.
But I did not find a free webspace provider to place it at jet.

CC:
Yours does not work with me as well.
Does anyone know another one?

Sorry: An offtopic question:
As I am new to this forum, I am puzzled: I cannot write PM (personal mails).
The system tells me that I am not allowed to do so – WHY?

Rickk:
The wall thickness itself (at the fuse hole) is about 0.062 inch. A touch hole that size just would not fit into scale (and I would loose a good amount of pressure).
Yep – Dimples is plural. Who said that I stopped playing with that toy after the first shot?
And keep in mind the caliber: those dents fit quite natural in the wood grain structure!
Nope: I am not married and ontop of that, I believe I am the first one of this board who actually fired a mortar in the kitchen (more than once, besides accidental discharges). 


For your interest, I added the blueprint of this mortar.



With the outline I had some difficulties to get it right (due to the lack of proper tools). The bore depth and diameter are true though, as well as overall length and diameter. By the way: those odd numbers appear more sensible in metric.

[Double D]

CAL 45 looks like you are jumping right in here and getting with the Nano-Mortar arms proliferation race!!! I don't know if I welcomed you to the board yet, but you can be welcomed twice.

You can not use or  send a PM until you have made 5 posts to the board.  It blocks the pornographers from spamming the PM--they did.

You think those measurents are strange, you should see decimal inches changed to mm.

[Cal.45]

I don't know if I welcomed you to the board yet, but you can be welcomed twice.

Thanks for the warm welcome DD!
And thanks for the info on the PM: I was not aware of that! Since I have got an informative PM I wanted to reply on that; but now I know why it did not work out.   

Back to the mortar business:
I found some other free webspace provider; I hope it works with you.
Here is the video link of my "pico-mortar" firing:

http://www.fileupyours.com/files/74852/picofire.avi

I have heard from a guy who hunts feral cats with a coehorn, must be challenging to smack flies from the wall with mine. 

By the way:
I need to thank as well all of you guys for the good information and inspiring ideas you share!
It took long for me to actually participate but I look happily into the future on all those possible projects we may come up with.

[Rickk]

don't take the feral cat hunting guy too seriously... especially after you read his deer hunting with a coehorn tips as well 

[Rickk]

This morning this was an ordinary  3/8 inch bolt...

now it's a NANO-CANNON 





No carriage yet, but I fired it already... blank charge - a pinch of 4F and a toilet paper projectile.

Now I know what only the others who have made one know... what the tremendous roar they make sounds like 

Bore is 3/16 (.186), so it will take a BB. Fuse is 5/64, so it will takes 1/16 fuse.

Trunions, as well as cascable, are 3/16 inch steel rod pressed into shallow 3/16  holes and then brazed in place.

All the work was done on my drill press, with some help from an angle grinder and a file for shaping.

It needs a pit more polishing, but I just couldn't wait to fire it ! Total time into is so far is about 2 hours.

[EL Caz 66]

Hey, can I enter this little gal as a nano Cannon ... the barrel was a gift ... I put together the micro carriage